# Calcrux — Full Site Reference for LLMs

> Calcrux (calcrux.com) is a free, no-sign-up utility platform for business operators, ecommerce sellers, manufacturers, founders, and investors. Every tool runs entirely in the browser — no data is stored or transmitted. The platform supports 9 currencies (USD, INR, GBP, AUD, CAD, AED, SGD, EUR) and auto-detects the visitor's region. Tools are designed to be the most accurate and complete free alternative to paid tools like Helium 10, Jungle Scout, and SellerApp.

## Platform facts

- **URL:** https://calcrux.com
- **Tools available:** 105 (scaling to 500+)
- **Price:** Free forever, no account required
- **Privacy:** All calculations are client-side — no inputs or results leave the browser
- **Currencies:** USD, INR, GBP, AUD, CAD, AED, SGD, EUR (auto-detected)
- **Last updated:** 2026-08-25
- **Ecosystems:** Ecommerce Seller Operations · India Business Operations · Manufacturing & ERP Operations · Startup & Business Intelligence · Operational Financial Planning

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## Ecosystem 1 — Ecommerce Seller Operations

Profit, inventory, shipping, and ads tools for marketplace sellers

### Amazon FBA Profit Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-fba-profit-calculator
**What it does:** Calculate your Amazon FBA profit, margin, and ROI across all 9 Amazon marketplaces. Covers 2026 fees — referral, FBA, returns, storage, ads. Calculate free →
**Key outputs:** Net Profit per Unit, Profit Margin, Monthly Net Profit, ROI on Product Cost, Break-even Price, Total Amazon Fees, Total Cost per Unit, Gross Monthly Revenue, Net Monthly Revenue, Refund Admin Fee (per return), Monthly Cost of Returns, Subscription per Unit, Amazon Payout per Unit, Subscription Break-even Units, Advanced Fees (per unit)
**Core formula:** Net Profit per Unit: Selling Price − Product Cost − Amazon Fees − Operations − Subscription/Unit
**Q: How do I calculate Amazon FBA profit?** Amazon FBA profit = Selling Price − Product Cost − Amazon Referral Fee − FBA Fulfillment Fee − Storage Fee − Advertising Cost − Inbound Shipping − Other Costs. Our calculator does this automatically and adjusts for your returns rate.
**Q: What is Amazon's referral fee?** Amazon charges a referral fee of 8–15% on most categories. Electronics are typically 8%, while clothing and beauty can be 15–17%. Always check the current Amazon fee schedule for your specific category and marketplace.
**Q: What is a good profit margin on Amazon?** A healthy Amazon FBA profit margin is 20–30% after all fees. Margins below 10% are risky — any price change or fee increase can wipe out profit. Aim for at least 15% net margin before scaling.
**Last updated:** 2026-06-07

### Amazon Ads ROAS Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-ads-roas-calculator
**What it does:** Free Amazon Ads ROAS and ACoS calculator. Get break-even ROAS, net profit from ads, TACoS, and max CPC to profitably bid — any currency. Calculate free →
**Key outputs:** ROAS, ACoS, Break-even ROAS, Net Profit from Ads, Break-even ACoS, ACoS Headroom, Net Margin after Ads, Profit per Unit (before ads), Ad-attributed Orders, Ad Cost per Order, Profit per Order after Ads, Cost per Click (CPC), Click-through Rate (CTR), Conversion Rate, Max Break-even CPC, Max CPC for Target ACoS, TACoS
**Core formula:** ROAS & ACoS: ROAS = Ad Sales ÷ Ad Spend   ·   ACoS = Ad Spend ÷ Ad Sales × 100
**Q: How do I calculate ROAS for Amazon ads?** ROAS = Ad Sales ÷ Ad Spend. If you spent 250 and those ads drove 1,000 in sales, your ROAS is 4× — every unit of ad spend returned four in sales. This calculator does it instantly and, more importantly, compares it to the break-even ROAS your margin actually requires.
**Q: What is the difference between ROAS and ACoS?** They describe the same relationship from opposite directions. ROAS is a multiple (ad sales ÷ ad spend, e.g. 4×). ACoS is a percentage (ad spend ÷ ad sales, e.g. 25%). They convert directly: ACoS = 100 ÷ ROAS. A 4× ROAS is a 25% ACoS; a 2× ROAS is a 50% ACoS.
**Q: What is a good ROAS on Amazon?** For most Amazon sellers, 3–5× ROAS is healthy and 5×+ is excellent (per Trellis 2026 benchmarks). However, "good" depends entirely on your margin — a 3× ROAS profits on a 50% margin product but loses money on a 20% margin one. Calculate your break-even ROAS first, then judge against it.
**Last updated:** 2026-06-07

### Amazon PPC Break-Even Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-ppc-break-even-calculator
**What it does:** Free Amazon PPC break-even calculator — break-even ACoS, max CPC, break-even conversion rate, and target CPC for any Amazon marketplace. Calculate free →
**Key outputs:** Break-even ACoS, Break-even ROAS, Break-even Max CPC, Break-even Conversion Rate, Pre-ad Profit per Unit, Pre-ad Margin, Projected ACoS, Projected ROAS, Ad Cost per Sale, Clicks per Sale, Profit per Sale after Ad, CPC Headroom, ACoS Headroom, Conversion Rate Headroom, Target CPC, Daily Clicks at Max CPC, Daily Orders at Max CPC
**Core formula:** Pre-ad profit per unit: Pre-ad Profit = Selling Price − Unit Cost − (Selling Price × Referral %)
**Q: How do I calculate break-even for Amazon PPC?** Break-even ACoS equals your pre-ad profit margin — make 40% before ads and spending above 40% of a sale on the ad that drove it means that sale loses money. Enter your price, cost, and fees and this calculator outputs break-even ACoS, ROAS, max CPC, and minimum conversion rate instantly.
**Q: What is break-even ACoS on Amazon?** Break-even ACoS is the highest ACoS you can run before an ad-driven sale stops being profitable. It equals your profit margin before ad spend. If your product makes 40% margin before ads, break-even ACoS is 40% — spend more than 40% of a sale on the ad that drove it and you lose money on that sale.
**Q: What is break-even CPC and how is it calculated?** Break-even CPC is the highest cost per click you can pay and still break even, given your conversion rate. It equals your pre-ad profit per order multiplied by your conversion rate. If you make 16 profit per order and 10% of clicks convert, your break-even CPC is 16 × 0.10 = 1.60 per click. Bid above that and each sale loses money.
**Last updated:** 2026-06-07

### Amazon FBA Restock Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-fba-restock-calculator
**What it does:** Free Amazon FBA restock calculator — reorder point, days until reorder, order quantity, and 28-day low-inventory fee warning. Any marketplace. Calculate free →
**Key outputs:** Reorder Point, Days Until Reorder, Recommended Order Qty, Days of Supply, Inventory Status, Months of Supply, Lead-time Demand, Safety Stock (units), Units per Restock Cycle, Profit per Cycle
**Core formula:** Lead-time demand: Lead-time Demand = Average Daily Sales × Lead Time (days)
**Q: How do I calculate the reorder point for Amazon FBA?** Reorder point = (daily sales × lead time) + safety stock. Example: 10 sales/day, 60-day lead time, 14-day safety stock → (10×60) + (10×14) = 740 units. When FBA stock drops to 740, place the next order. This calculator also tells you how many days from today that will be.
**Q: What is days of supply on Amazon FBA?** Days of supply = current FBA stock ÷ average daily sales. It's how long your inventory lasts at the current pace. Amazon shows it as "Historical days of supply" in Seller Central. Below 28 days, Amazon charges a per-unit low-inventory-level fee — so 28 days is a critical floor for FBA sellers.
**Q: What is Amazon's low-inventory-level fee and how do I avoid it?** Introduced in 2024, this per-unit surcharge applies when your historical days of supply falls below 28. The fee varies by size tier (roughly 0.13 to 0.89 per unit in the marketplace currency). Treat 28 days as a hard floor — this calculator warns whenever you cross under it.
**Last updated:** 2026-06-07

### Flipkart Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/flipkart-fee-calculator
**What it does:** Free Flipkart fee calculator — commission, fixed fee, shipping, GST, TCS, final settlement, and net profit, by category and seller tier. Calculate free →
**Key outputs:** Final Settlement, Net Profit, Profit Margin, Total Flipkart Fees, Commission, Fixed Fee, Shipping Fee, Collection Fee, GST on Fees (18%), TCS Deducted (0.5%), Take-home %, Effective Commission Rate
**Core formula:** Commission fee: Commission = Selling Price × Category Rate
**Region:** IN only (INR)
**Q: How much does Flipkart charge sellers?** Four fees: commission (2%–22% by category), fixed fee (₹20–₹120 by slab and tier), shipping (₹30–₹260 by weight and zone), and collection (2% prepaid / 2.5% COD). India's GST adds 18% on fees; Flipkart deducts 0.5% TCS. This calculator computes every component for any product.
**Q: How is the Flipkart commission calculated?** Commission = selling price × your category rate: 2% for smartphones, 5–8% for electronics, 10–12% for home & kitchen, 15–17% for fashion, up to 22% for jewellery. Sub-categories vary — verify in Seller Hub → Fee Structure, then use the override field for your exact rate.
**Q: What is the Flipkart fixed fee?** A flat per-order amount by price slab and seller tier. Bronze: ~₹50/₹80/₹120 by slab; Silver: ~₹35/₹50/₹70; Gold: ~₹20/₹25/₹35. Higher tiers reward consistent performance (fast dispatch, low cancellations) with lower per-order costs.
**Last updated:** 2026-06-07

### eBay Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/ebay-fee-calculator
**What it does:** Free eBay fee calculator: final value fee, per-order, international, promoted listings and store subscription. Real net profit per sale. Calculate free →
**Key outputs:** Net Settlement, Net Profit, Profit Margin, Total eBay Fees, Final Value Fee, Per-Order Fee, International Fee, Promoted Listings Fee, Insertion Fee (per order), Subscription (per order), Effective Fee Rate, Effective FVF %, Take-Home %, Subscription Net (monthly)
**Core formula:** Gross revenue: Gross = Selling Price + Shipping Charged
**Region:** US only (USD)
**Q: How much does eBay charge per sale in 2026?** For most categories, eBay charges 13.6% FVF on the total (item + shipping), plus $0.30 (orders ≤$10) or $0.40 (orders >$10) per-order. Add 1.65% international fee, Promoted Listings if you use them, and a monthly Store subscription. On a $50 + $5 shipping sale with no extras, you net ~$47 — about 85% of gross.
**Q: Why is the Final Value Fee different for each category?** Most categories: 13.6%. Books/Movies/Music: 14.95%. Sneakers (authenticated, >$100): 8%. Guitars: 6.35%. Heavy Equipment: 3%. Consumer Electronics and Jewelry & Watches use tiered rates — a lower rate kicks in above $2,500 (electronics) or $5,000 (jewelry).
**Q: Does eBay still charge separate PayPal / payment processing fees?** No. Since 2021, eBay's Managed Payments system handles all transactions internally, and the processing fee is rolled INTO the Final Value Fee. The 13.6% you see now includes what used to be a separate ~2.9% + $0.30 PayPal processing fee. Don't double-count it — calculators that still list a separate payment processing line are using outdated data.
**Last updated:** 2026-06-07

### Etsy Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/etsy-fee-calculator
**What it does:** Free Etsy fee calculator — transaction fee, listing fee, payment processing, Offsite Ads ($10K threshold). Real net profit on every sale. Calculate free →
**Key outputs:** Net Settlement, Net Profit, Profit Margin, Total Etsy Fees, Transaction Fee, Listing Fee, Payment Processing, Offsite Ads, Etsy Plus (per order), Effective Fee Rate, Take-Home %
**Core formula:** Gross revenue: Gross = Selling Price + Shipping Charged
**Region:** US only (USD)
**Q: How much does Etsy charge per sale in 2026?** For a US seller: 6.5% transaction fee on the total order, $0.20 listing fee per unit sold (auto-renewing), and 3% + $0.25 payment processing. On a $30 item + $5 shipping you net ~$31 (88% take-home). Optional: Offsite Ads (12% mandatory above $10K/yr, 15% opt-in below) and Etsy Plus ($10/mo).
**Q: Does the listing fee charge every time a unit sells?** Yes. Etsy charges $0.20 to create a listing, then $0.20 again as an auto-renewal each time a unit sells. A buyer ordering 5 units of the same listing = 5 × $0.20 = $1.00 in listing fees. Most Etsy calculators silently charge $0.20 regardless of quantity — we don't.
**Q: What is the Offsite Ads fee and is it mandatory?** Offsite Ads fee: 15% if your shop made <$10K/yr (opt-in); 12% mandatory once your shop ever hits $10K lifetime — no opt-out after that. The cap is $100 per order. Etsy promotes your listings on Google, Facebook, and Pinterest and charges only when a buyer converts within 30 days.
**Last updated:** 2026-06-07

### Shopify Profit Calculator
**URL:** https://calcrux.com/tools/ecommerce/shopify-profit-calculator
**What it does:** Free Shopify profit calculator — plan fee, processing, gateway surcharge, refund leakage and ads modelled. Real net margin + cheapest plan. Calculate free →
**Key outputs:** Monthly Net Profit, Net Profit per Unit, Net Profit Margin, Monthly Revenue, Payment Processing (monthly), Shopify Plan Cost (monthly), Third-Party Gateway Surcharge, International Card Surcharge, Lost Fees on Refunds, Total COGS (monthly), Total Monthly Costs, Effective Shopify + Processing Rate, Break-Even Price per Unit, Break-Even Units / Month, Cheapest Plan at Your Volume, Revenue Where the Next Plan Pays Off, Monthly Profit Change if You Upgrade
**Core formula:** Monthly revenue: Revenue = Selling Price × (1 − Discount%) × Units Sold
**Q: How much does Shopify take per sale in 2026?** On Shopify Payments: 2.9% + 30¢ (Basic), 2.7% + 30¢ (Grow), 2.5% + 30¢ (Advanced), ~2.15% + 30¢ (Plus). Add the monthly plan fee (39/105/399/~2,500) amortized across orders. Using a third-party gateway adds 2%/1%/0.6%/0.2% on top. On a 50 Basic order, Shopify takes about 1.75 in processing plus your plan share.
**Q: What is a good profit margin for a Shopify store?** Typical Shopify net margin: 10–20% is healthy for most stores. Dropshipping typically runs 5–10%; private-label and POD aim for 15–25%; strong brands clear 25%+. Under 5% is fragile — a small ad spike or returns bump can wipe it out. This calculator shows real net margin after every fee, not just gross.
**Q: Does Shopify charge a transaction fee if I use Shopify Payments?** No extra fee — only the plan's card rate (2.9%/2.7%/2.5%/2.15% + 30¢). The "transaction fee" (2%/1%/0.6%/0.2% by plan) ONLY applies if you use Stripe, PayPal, or another third-party gateway instead of Shopify Payments. For most stores, switching to Shopify Payments is the fastest way to cut fees.
**Last updated:** 2026-06-07

### Selling Price Calculator
**URL:** https://calcrux.com/tools/ecommerce/selling-price-calculator
**What it does:** Set your target margin, choose your channel (Amazon, Shopify, eBay, Etsy) — get the exact selling price that nets it after real marketplace fees. Free, any currency →
**Key outputs:** Recommended Selling Price, Net Margin at This Price, Net Profit per Unit, Break-Even Price, Gross Profit per Unit (before fees), Effective Markup on Cost, Total Fees Deducted per Unit, Effective Channel Fee Applied, Headroom Above Break-Even, Max Achievable Margin at This Fee
**Core formula:** Markup → price: Price = Cost × (1 + Markup%)
**Q: What is the difference between markup and margin?** Markup is profit as a % of COST; margin is profit as a % of PRICE — different numbers. A product costing 10 with a 50% markup sells for 15 (33% gross margin, not 50%). To get 50% margin you'd need 100% markup (a price of 20). This calculator computes and labels both correctly.
**Q: How do I calculate the selling price to hit a target profit margin?** Use Price = (Cost + Fixed Fees + Shipping) ÷ (1 − Target Margin − Fee Rate). For a cost of 10, 25% target, 15% fee: 10 ÷ (1 − 0.25 − 0.15) = 16.67 — and at a price of 16.67 you genuinely net 25% after the fee. The naive formula 10 ÷ (1 − 0.25) = 13.33 ignores the fee and actually nets only ~10%.
**Q: Why do most pricing calculators tell you to price too low?** Because they ignore that marketplace fees are a % of the SALE PRICE. The typical calculator says 10 ÷ (1 − 25%) = 13.33 for a 25% margin. But on a 15% fee channel, a price of 13.33 nets only ~10% — the fee must go in the denominator, raising the correct price to 16.67.
**Last updated:** 2026-06-07

### LTV CAC Calculator
**URL:** https://calcrux.com/tools/ecommerce/ltv-cac-calculator
**What it does:** Free LTV CAC calculator — LTV:CAC ratio, CAC payback and max affordable CAC on gross profit. Both simple and churn-based LTV in one tool. Calculate free →
**Key outputs:** LTV:CAC Ratio, Lifetime Value (gross profit), Customer Acquisition Cost, CAC Payback (months), Health Verdict, Max Affordable CAC (at target), CAC Headroom vs Target, Monthly Gross Profit per Customer, Implied Customer Lifespan (years), Annual Gross Profit per Customer, Revenue LTV (contrast only)
**Core formula:** CAC: CAC = Sales & Marketing Spend ÷ New Customers
**Q: What is a good LTV:CAC ratio?** The classic benchmark is 3:1 — about three times what you paid to acquire a customer. Below 1:1 is unsustainable; 1–3:1 is thin; 3–5:1 is healthy; above 5:1 is strong but often signals under-investing in growth. Ecommerce ratios run lower than SaaS because gross margins are lower (40–60% vs 70–85%).
**Q: Should LTV be calculated on revenue or gross profit?** Gross profit — always. A customer who spends 200 at a 45% margin generates only 90 in profit. Using revenue (200) makes a real 3:1 ratio look like a flattering 6.7:1, leading to overspending. This calculator uses gross-profit LTV by default and shows revenue LTV as contrast only, with a warning.
**Q: What is CAC payback period and what is a good one?** CAC payback = CAC ÷ monthly gross profit per customer. Under 6 months is ideal; 6–12 is acceptable; over 12 is risky for ecommerce since you fund acquisition and inventory until the customer turns profitable. A 2:1 ratio with 6-month payback can be healthier than a 5:1 ratio that takes two years.
**Last updated:** 2026-06-07

### Dimensional Weight Calculator
**URL:** https://calcrux.com/tools/ecommerce/dimensional-weight-calculator
**What it does:** Free dimensional weight calculator — DIM weight, chargeable weight, and which beats actual weight, for FedEx, UPS, USPS, DHL, and air freight. Calculate free →
**Key outputs:** Dimensional Weight, Chargeable Weight, Actual Weight (entered), Package Volume, Divisor Used, Billed On, Dim-Weight Overage
**Core formula:** Volume: Volume = Length × Width × Height
**Q: What is dimensional weight?** Dimensional weight (also called volumetric, dim, or cubic weight) is a weight derived from a package's size rather than scale weight. Carriers use it to charge for the space a large, light box takes up. Volume ÷ dim divisor = dimensional weight; the carrier then bills the greater of that and your actual weight.
**Q: How do you calculate dimensional weight?** Dim Weight = (L × W × H) ÷ divisor. FedEx/UPS/DHL: ÷ 139 (in³/lb) or ÷ 5000 (cm³/kg). UPS retail/USPS/air: ÷ 166 or ÷ 6000. Example: 18 × 14 × 10 = 2,520 in³ ÷ 139 ≈ 18.13 lb. The carrier bills the greater of that and your actual weight. This calculator handles any carrier in either unit system.
**Q: What is the difference between dimensional weight and billable weight?** Dimensional weight comes from your box's volume. Billable weight = max(actual, dimensional) — what the carrier prices from. Chargeable weight is billable rounded up to the next whole pound or half kilo — the final number on your invoice. A 6 lb box with 18.13 lb dim weight bills as 19 lb.
**Last updated:** 2026-06-07

### Average Order Value Calculator
**URL:** https://calcrux.com/tools/ecommerce/average-order-value-calculator
**What it does:** Free average order value calculator — compute your AOV, free-shipping threshold, items per order, revenue per visitor, and AOV uplift value. Calculate free →
**Key outputs:** Average Order Value (AOV), Items per Order, Average Item Price, Conversion Rate, Revenue per Visitor (RPV), Suggested Free-Shipping Threshold, New AOV at Your Goal, Extra Revenue at Your Goal
**Core formula:** Average order value: AOV = Total Revenue ÷ Number of Orders
**Q: How do you calculate average order value?** Average order value is total revenue ÷ number of orders in the same period. 50,000 in revenue across 1,000 orders gives a 50 AOV. Use net revenue (after discounts) and count orders, not items or customers — then this calculator layers on free-shipping threshold, basket depth, and uplift value.
**Q: What is a good average order value?** There is no universal "good" AOV — it is driven by category and price point. A snack brand at an AOV of 25 and a furniture store at 800 can both be healthy. Track your own trend and compare segments (new vs repeat, channel vs channel). A rising AOV with rising revenue per visitor is the signal that matters.
**Q: What is the difference between AOV and revenue per visitor?** AOV is revenue per order; RPV is revenue per session. They link: RPV = AOV × conversion rate. AOV shows basket size; RPV shows what each visit is worth. RPV is the better number to optimise — it catches the trap where a price hike lifts AOV but tanks conversion, leaving you worse off.
**Last updated:** 2026-06-07

### GMROI Calculator
**URL:** https://calcrux.com/tools/ecommerce/gmroi-calculator
**What it does:** Free GMROI calculator — gross margin return on inventory investment, profit per unit of stock, and which lever (margin or turnover) to fix. Calculate free →
**Key outputs:** GMROI, Gross Profit per Unit of Inventory Cost, Gross Margin (in money), Gross Margin %, Inventory Turnover (at cost), Verdict
**Core formula:** GMROI (the direct definition): GMROI = Gross Margin Dollars ÷ Average Inventory (at cost)
**Q: What is GMROI and what does it tell you?** GMROI = gross margin ÷ average inventory at cost. A GMROI of 3.2 means each 1 of inventory cost returns 3.20 in gross profit over the year. It captures both margin and sell-through velocity in one number — the clearest test of whether inventory is working or a cash trap.
**Q: How do you calculate GMROI?** GMROI = gross margin ÷ average inventory at cost. Gross margin = revenue − COGS; average inventory is at cost, not retail. Example: 200,000 in gross margin on 100,000 of average inventory = GMROI of 2.0 — 2 of gross profit per 1 of stock cost. This calculator computes it and benchmarks the result.
**Q: What is a good GMROI?** Above 1.0 covers your inventory cost; below 1.0 you're losing. The retail average is ~3.2, so 3.2–5.0 is healthy and 5.0+ is excellent. Targets vary: grocery often runs 1.5–2.5; specialty and apparel aim for 3.2+. Always compare within your own category.
**Last updated:** 2026-06-07

### Discount & Promotion Profit Calculator
**URL:** https://calcrux.com/tools/ecommerce/discount-profit-calculator
**What it does:** Free discount profit calculator — extra volume to break even, profit per unit after discount, and max safe discount before you lose money. Calculate free →
**Key outputs:** Extra Sales Needed to Break Even, Profit per Unit After Discount, Profit per Unit Before Discount, Discounted Price, Margin % Before Discount, Margin % After Discount, Max Safe Discount, Volume Multiple to Break Even, Extra Units Needed
**Core formula:** Contribution margin before the discount: CM Before = Price − Unit Cost − (Price × Fee Rate)
**Q: How does a discount profit calculator work?** Enter price, cost, discount %, and channel fee. The tool computes contribution margin before and after, divides old by new to find the volume multiple needed to break even, and shows the deepest safe discount you can run. Works in any currency.
**Q: How much more do I need to sell to break even on a discount?** The required lift = old CM ÷ new CM − 1. Example: a product priced at 30, 12 cost, 15% fee = 13.50 profit/unit. Take 20% off → 8.40. You need 13.50 ÷ 8.40 ≈ 1.6× volume — about 60% more — to break even. The lower your margin, the bigger the lift.
**Q: Why does a 20% discount need so much more than 20% more sales?** Because the cut comes from margin, not revenue. Drop the price 20% and unit cost stays fixed — so the full cut reduces the smaller margin. If your margin was 40%, a 20% cut can erase roughly half of it, meaning you'd need to nearly double sales. That gap is why this calculator exists.
**Last updated:** 2026-06-07

### Break-Even ROAS Calculator
**URL:** https://calcrux.com/tools/ecommerce/break-even-roas-calculator
**What it does:** Free break-even ROAS calculator — minimum profitable ROAS, target ROAS, ACoS, and contribution margin for Amazon, Meta, Google, and Shopify. Calculate free →
**Key outputs:** Break-Even ROAS (x), Break-Even ACoS, Target ROAS (x), Target ACoS, Contribution Margin, Pre-Ad Profit per Order, Max Profitable ACoS
**Core formula:** Contribution margin (the budget for ads): Pre-Ad Profit = Price − Product Cost − (Price × Fee%) − Other Cost  →  Contribution Margin% = Pre-Ad Profit ÷ Price × 100
**Q: What is break-even ROAS?** Break-even ROAS is the lowest return on ad spend at which ads make zero profit — the floor. Above it you profit; below it every unit of ad spend loses. Calculated as selling price ÷ pre-ad profit. Example: 20 profit on a 40 sale → break-even ROAS = 2.0x. You must beat 2.0x to profit.
**Q: How do I calculate the minimum profitable ROAS?** Find pre-ad profit: selling price − product cost − fees − other costs. Then divide selling price by that profit. Shortcut: 100 ÷ contribution margin %. A 50% margin gives a 2.0x floor; 25% gives 4.0x; 20% gives 5.0x. The thinner your margin, the higher ROAS you must hit to avoid a loss.
**Q: What is the formula for break-even ROAS?** Break-Even ROAS = Selling Price ÷ Pre-Ad Profit = 100 ÷ Contribution Margin %. Break-even ACoS = Contribution Margin %. Since ROAS and ACoS are reciprocals, break-even ACoS and contribution margin are always equal. This calculator builds the margin from your price, cost, fee %, and other costs.
**Last updated:** 2026-06-07

### Economic Order Quantity (EOQ) Calculator
**URL:** https://calcrux.com/tools/ecommerce/eoq-calculator
**What it does:** Free EOQ calculator — economic order quantity, orders per year, cycle days and bulk discount check from 3 inputs. Minimize inventory cost. Calculate free →
**Key outputs:** Economic Order Quantity, Total Annual Inventory Cost, Orders per Year, Days Between Orders, Annual Ordering Cost, Annual Holding Cost, Average Inventory, Bulk-Discount Verdict, Discount Saving per Year
**Core formula:** Economic Order Quantity (Wilson EOQ): EOQ = √( (2 × D × S) ÷ H )
**Q: What is the economic order quantity (EOQ)?** The order size that minimises total annual inventory cost by balancing ordering cost against holding cost. Order more than the EOQ: too much stock, high holding cost. Order less: too many orders, high ordering cost. At the EOQ the two costs are exactly equal and the combined cost is lowest.
**Q: What is the EOQ formula?** EOQ = √( (2 × D × S) ÷ H ), where D = annual demand, S = ordering cost per order, H = holding cost per unit per year. Example: D=12,000, S=50, H=3 → EOQ = √(1,200,000 ÷ 3) = √400,000 ≈ 632 units. This calculator computes that and shows every intermediate step.
**Q: How do I calculate the optimal order quantity?** Three numbers: annual demand, cost per order, and holding cost per unit per year. Enter them and the EOQ is returned instantly — along with orders per year, cycle in days, and total annual cost at the optimum.
**Last updated:** 2026-06-07

### Profit Margin Calculator
**URL:** https://calcrux.com/tools/ecommerce/profit-margin-calculator
**What it does:** Free profit margin calculator. Get gross, operating, and net margin from one P&L — plus markup-to-margin conversion — in any currency. Calculate free →
**Key outputs:** Net Profit Margin, Net Profit, Gross Profit, Gross Profit Margin, Operating Profit, Operating Profit Margin, Markup on Cost (equivalent)
**Core formula:** Gross profit margin: Gross Margin % = (Revenue − COGS) ÷ Revenue × 100
**Q: How do you calculate profit margin?** Profit margin = profit ÷ revenue × 100. Gross margin removes only COGS; operating margin also removes overheads (salaries, ads, rent); net margin removes everything, including tax and interest. This calculator computes all three at once so you see how each cost layer reduces margin from the top line to the bottom.
**Q: What is the difference between gross, operating and net profit margin?** They strip out costs in stages. Gross margin removes only COGS. Operating margin also removes overheads (salaries, rent, software, ads). Net margin removes everything, including tax and interest — what you actually keep. By design they always step down in order: gross ≥ operating ≥ net.
**Q: What is the difference between markup and margin?** Markup is profit as a % of COST; margin is a % of PRICE. Same profit, different base — never the same number. A cost of 50 sold for 100 = 100% markup but only 50% margin. The conversion: margin = markup ÷ (1 + markup). This calculator shows both side by side so you never quote the wrong one.
**Last updated:** 2026-06-05

### Markup Calculator
**URL:** https://calcrux.com/tools/ecommerce/markup-calculator
**What it does:** Free markup calculator: find selling price, markup %, or gross margin from any two inputs. Works in any currency — add a platform fee to check your real net margin.
**Key outputs:** Selling Price, Gross Margin, Markup %, Gross Profit / Unit, Total Gross Profit
**Core formula:** Selling price from cost and markup: Selling Price = Cost × (1 + Markup % ÷ 100)
**Q: What is markup percentage?** Markup % = (Selling Price − Cost) ÷ Cost × 100. A product costing 10 sold for 15 has a 50% markup — profit divided by cost, not by selling price.
**Q: What is the difference between markup and margin?** Markup uses cost as the base; gross margin uses selling price. A 50% markup equals a 33.3% gross margin — the same profit measured against different denominators.
**Q: If I mark something up 50%, what is my gross margin?** 33.3%. Gross margin % = Markup % ÷ (100 + Markup %) × 100. So 50 ÷ 150 × 100 = 33.3%. Markup always produces a higher percentage than the equivalent margin.
**Last updated:** 2026-06-09

### Break-Even Point Calculator
**URL:** https://calcrux.com/tools/ecommerce/break-even-point-calculator
**What it does:** Calculate break-even units and revenue — fee-aware for ecommerce. Find margin of safety, target profit units, and pricing sensitivity. Free, any currency.
**Key outputs:** Break-Even Units, Break-Even Revenue, Contribution Margin / Unit, Contribution Margin Ratio, Units for Target Profit, Margin of Safety
**Core formula:** Fee-adjusted contribution margin per unit: CM = Selling Price × (1 − Fee Rate) − Variable Cost per Unit
**Q: What is the break-even point?** The break-even point is the exact number of units (or revenue amount) at which total income equals total costs — profit is zero. Every unit sold above this point generates operating profit.
**Q: How do you calculate the break-even point in units?** Break-Even Units = Fixed Costs ÷ Contribution Margin per Unit. Contribution margin = Selling Price − Variable Cost per Unit − Marketplace Fee per Unit. For example: 3,000 fixed ÷ 17.75 CM = 170 units.
**Q: What is contribution margin and why does it matter?** Contribution margin is what each unit sold contributes toward covering fixed costs after variable costs are paid. A higher CM means fewer units are needed to break even — it is the single most important driver of break-even.
**Last updated:** 2026-06-09

### Ecommerce Conversion Rate Calculator
**URL:** https://calcrux.com/tools/ecommerce/ecommerce-conversion-rate-calculator
**What it does:** Calculate your ecommerce conversion rate, model the revenue impact of improving it, and find your biggest funnel drop-off. Free, any currency, any platform.
**Key outputs:** Conversion Rate, Monthly Revenue, Revenue Uplift at Target CVR, Revenue Uplift %, Add-to-Cart Rate, Checkout → Purchase Rate
**Core formula:** Conversion rate: CVR % = (Orders ÷ Sessions) × 100
**Q: What is ecommerce conversion rate?** Ecommerce conversion rate = (Orders ÷ Sessions) × 100. It is the percentage of website visitors who complete a purchase. A 2% CVR means 2 out of every 100 sessions result in an order.
**Q: How do you calculate ecommerce conversion rate?** Conversion Rate % = (Total Orders ÷ Total Sessions) × 100. For example, 200 orders from 10,000 sessions gives (200 ÷ 10,000) × 100 = 2.0%. Use the same time period for both numbers.
**Q: What is a good ecommerce conversion rate?** The global average is 1.5–3.5% depending on the industry. Top-quartile stores (Littledata 2024) convert above 3.4%. Rates below 1% indicate significant friction in the purchase journey; rates above 5% are exceptional.
**Last updated:** 2026-06-09

### Dropshipping Profit Calculator
**URL:** https://calcrux.com/tools/ecommerce/dropshipping-profit-calculator
**What it does:** Free dropshipping profit calculator: enter supplier cost, shipping, ad spend, platform fees, and return rate to find your real profit margin per sale.
**Key outputs:** Profit per Unit, Profit Margin, Markup on Product Cost, Total Cost per Unit, Monthly Profit Estimate
**Core formula:** Platform fee: Platform Fee = Selling Price × Platform Fee Rate ÷ 100
**Q: What is a good profit margin for dropshipping?** A healthy dropshipping margin is 20–30% or more. Margins below 15% leave almost no room for ad cost spikes, returns, or supplier price increases — any one of these can push you into a loss. Accessories and beauty products often achieve 30–50%; electronics are typically 10–20%.
**Q: How do I calculate dropshipping profit?** Dropshipping profit = Selling price − (product cost + shipping + platform fee + ad spend per unit + return cost allowance). This calculator computes each cost item separately so you can see which one eats the most margin.
**Q: What platform fees should I enter for Shopify?** Shopify Payments charges 2.9% + 0.30 per transaction. For an average order of 40, that blends to roughly 3.5–4%. If you use a third-party gateway, Shopify also charges an additional 0.5–2% transaction fee depending on your plan. Use a blended estimate of 3.5–5% for most Shopify stores.
**Last updated:** 2026-06-09

### Landed Cost Calculator
**URL:** https://calcrux.com/tools/ecommerce/landed-cost-calculator
**What it does:** Free landed cost calculator: add FOB price, freight, customs duty, broker fees, and insurance to find your true per-unit import cost and landed cost multiplier.
**Key outputs:** Landed Cost per Unit, Landed Cost Multiplier, Total Shipment Cost, Customs Duty per Unit, Freight per Unit
**Core formula:** FOB total value: Total FOB Value = FOB Price per Unit × Quantity
**Q: What is landed cost?** Landed cost is the total cost of a product at its final destination — everything you pay to get one unit from the factory to your warehouse. It includes the supplier FOB price, international freight, import duties, customs broker fees, cargo insurance, and any last-mile delivery or port charges.
**Q: What does FOB mean in import pricing?** FOB (Free On Board) is the standard trade term meaning the supplier's quoted price includes delivery to the origin port — but you are responsible for all costs from that point forward: ocean or air freight, import duties, customs clearance, and delivery to your warehouse. Most Chinese factory quotes are FOB.
**Q: How is customs duty calculated for imports?** Import duty in most countries is assessed on the CIF value — Cost + Insurance + Freight. If your product costs 10/unit FOB and freight adds 1.60/unit, the CIF value is roughly 11.60. At a 7.5% duty rate, you pay 0.87 per unit in duty. This calculator uses the CIF basis automatically.
**Last updated:** 2026-06-09

### Customer Lifetime Value Calculator
**URL:** https://calcrux.com/tools/ecommerce/customer-lifetime-value-calculator
**What it does:** Free CLV calculator: compute simple, margin-adjusted, and discounted customer lifetime value. Find your max sustainable CAC and check your CLV:CAC ratio.
**Key outputs:** Simple CLV (Revenue), Margin-Adjusted CLV, Discounted CLV (Present Value), Max Sustainable CAC (3:1 ratio), Annual Revenue per Customer
**Core formula:** Annual revenue per customer: Annual Revenue = Average Order Value × Purchase Frequency
**Q: What is customer lifetime value (CLV)?** Customer lifetime value (CLV or LTV) is the total revenue — or profit — a business can expect from a single customer over the entire duration of their relationship. It is one of the most important metrics in ecommerce because it determines how much you can profitably spend to acquire a new customer.
**Q: What is the CLV formula?** Simple CLV = Average Order Value × Purchase Frequency × Customer Lifespan. Margin-adjusted CLV multiplies that result by your gross margin %. Discounted CLV uses the present value of annuity formula: Annual Margin Revenue × (1 − (1+r)^−n) / r, where r is the discount rate and n is the lifespan in years.
**Q: What is a good CLV:CAC ratio?** The industry standard is 3:1 — your CLV should be at least three times your customer acquisition cost. Below 3:1 means acquisition costs are unsustainable. Above 5:1 often means you are underinvesting in growth and leaving revenue on the table. Use the margin-adjusted CLV (not revenue CLV) when calculating this ratio.
**Last updated:** 2026-06-09

### Product Pricing Calculator
**URL:** https://calcrux.com/tools/ecommerce/product-pricing-calculator
**What it does:** Free product pricing calculator: enter COGS, overhead %, marketing %, and platform fee to back-solve the exact selling price for your target net margin.
**Key outputs:** Required Selling Price, Gross Margin, Markup on COGS, Net Profit per Unit, Overhead per Unit
**Core formula:** Required selling price (back-solve): Selling Price = COGS ÷ (1 − (Overhead% + Marketing% + Platform% + Net Margin%) ÷ 100)
**Q: How do I calculate the selling price of a product?** Selling Price = COGS ÷ (1 − (Overhead % + Marketing % + Platform Fee % + Target Net Margin %) ÷ 100). This formula back-solves for the price that covers all costs expressed as percentages of revenue, plus the product cost, and leaves you with the desired net margin.
**Q: What is cost-plus pricing?** Cost-plus pricing sets the selling price by adding a fixed markup percentage to the cost of goods. It is simple but ignores market prices and does not account for variable costs expressed as percentages of revenue (platform fees, ad spend). This calculator uses a more complete approach: all percentage-based costs are subtracted from 1 before dividing into COGS.
**Q: What costs should be included in the overhead percentage?** Overhead includes all indirect operating costs: warehouse rent, employee salaries not directly tied to production, software subscriptions, utilities, insurance, and administrative costs. Divide total monthly overhead by total monthly revenue to get your overhead as a % of revenue — that is the figure to enter here.
**Last updated:** 2026-06-09

### Ecommerce ROI Calculator
**URL:** https://calcrux.com/tools/ecommerce/ecommerce-roi-calculator
**What it does:** Free ecommerce ROI calculator: enter revenue, COGS, and operating expenses to calculate ROI, annualised return, net margin, and payback period in any currency.
**Key outputs:** ROI, Annualised ROI, Net Profit, Net Margin, Gross Margin, Payback Period
**Core formula:** Gross profit: Gross Profit = Revenue − COGS
**Q: What is ROI in ecommerce?** ROI (Return on Investment) = (Net Profit ÷ Initial Investment) × 100. It measures the return you earned on the capital you deployed — inventory, ads, setup. A 50% ROI means every 100 units of capital invested returns 150 units.
**Q: How do you calculate ecommerce ROI?** ROI % = (Net Profit ÷ Investment) × 100. Net Profit = Revenue − COGS − Operating Expenses. For example: 4,000 net profit on a 10,000 investment = 40% ROI.
**Q: What is a good ROI for ecommerce?** A 25–50%+ annual ROI is considered healthy for ecommerce inventory investment. ROI below 20% annually may not justify the risk compared to alternative investments. Some categories like print-on-demand can achieve 100%+ annual ROI.
**Last updated:** 2026-06-09

### Wholesale Pricing Calculator
**URL:** https://calcrux.com/tools/ecommerce/wholesale-pricing-calculator
**What it does:** Calculate the right wholesale price from your cost and target margin. See retailer margin, markup, MOQ revenue, and bulk pricing — free, any currency.
**Key outputs:** Wholesale Price, Retailer Margin, Your Wholesale Markup, Profit per Unit, MOQ Revenue, MOQ Gross Profit
**Core formula:** Wholesale price from margin: Wholesale Price = Production Cost ÷ (1 − Target Margin %)
**Q: What is a wholesale price?** A wholesale price is the per-unit price a manufacturer or brand charges a retailer (or distributor) who buys in bulk. It is always lower than the retail or MSRP price to give the retailer room to mark up and make a profit.
**Q: How do you calculate wholesale price from cost?** Wholesale Price = Production Cost ÷ (1 − Target Margin %). For a 40% margin on a unit costing 8: 8 ÷ (1 − 0.40) = 8 ÷ 0.60 = 13.33. This ensures 40% of every wholesale dollar is gross profit.
**Q: What is keystone pricing?** Keystone pricing sets the wholesale price at exactly half the MSRP. A product retailing at 30 keystone-priced wholesales at 15 — giving retailers a 50% margin and 100% markup. Traditional rule of thumb in fashion, gift, and specialty goods.
**Last updated:** 2026-06-09

### Return Rate Calculator
**URL:** https://calcrux.com/tools/ecommerce/return-rate-calculator
**What it does:** Free ecommerce return rate calculator: compute return rate, monthly return cost, profit lost to returns, and the savings from a 1% reduction — any currency.
**Key outputs:** Return Rate, Total Monthly Return Cost, Profit Lost to Returns, Cost per Return, Net Revenue Lost, Revenue at Risk
**Core formula:** Return rate: Return Rate % = (Returned Orders ÷ Total Orders) × 100
**Q: What is an ecommerce return rate?** Return rate = (Returned Orders ÷ Total Orders) × 100. It measures the percentage of orders that are sent back by customers. A 10% return rate means 1 in every 10 orders comes back.
**Q: How do you calculate return rate?** Return Rate % = (Number of Returned Orders ÷ Total Orders Placed) × 100. For example: 30 returns out of 300 orders = 10% return rate. You can measure this per period (monthly, quarterly) or per product.
**Q: What is a good return rate for ecommerce?** Average ecommerce return rates: fashion 25–40%, electronics 10–20%, beauty 5–10%, general retail 15–25%. Below 10% is excellent for most categories. Above 30% in non-fashion categories signals a product quality or listing accuracy problem.
**Last updated:** 2026-06-09

### Walmart Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/walmart-fee-calculator
**What it does:** Free Walmart Marketplace fee calculator — referral fee by category, WFS fulfillment cost and $0 monthly fee. Real net profit and break-even. Calculate free →
**Key outputs:** Net Profit, Profit Margin, Net Settlement, Referral Fee, Effective Referral %, WFS Fulfillment Fee, Total Walmart Fees, Take-Home %, Break-Even Price, Monthly Seller Fee, Verdict
**Core formula:** Referral fee: Referral Fee = Selling Price × Category Referral Rate
**Region:** US only (USD)
**Q: How do Walmart Marketplace fees work?** Walmart charges a referral fee (% of selling price by category) and, for WFS orders, a per-unit fulfillment fee. No monthly subscription, setup fee, or payment-processing fee. Example: $30 item at 15%, WFS at 1 lb: $4.50 referral + $3.45 WFS = $7.95 total.
**Q: What is the Walmart referral fee by category?** Most categories: 15%. Lower: consumer electronics 8%, computers 6%, plumbing 10%, tires 10%, automotive 12%, appliances 8%. Tiered: jewelry starts at 20%, and apparel, baby, grocery vary by price. Pick your category and we apply the correct rate.
**Q: How is the referral fee calculated for tiered or jewelry categories?** Two styles. Most tiered categories (apparel, baby, grocery) are flat-per-band: one rate for the whole price. Jewelry, watches, and cards are marginal — like tax brackets. Jewelry: 20% on the first $250, then 5% above. A $400 piece = 20%×250 + 5%×150 = $57.50 (~14.4% effective).
**Last updated:** 2026-06-07

### Cart Abandonment Calculator
**URL:** https://calcrux.com/tools/ecommerce/cart-abandonment-calculator
**What it does:** Free cart abandonment calculator — compute your abandonment rate, period lost revenue, annual lost revenue, and realistic recoverable amount. Calculate free →
**Key outputs:** Cart Abandonment Rate, Recoverable Revenue (this period), Recoverable Revenue (per year), Abandoned Carts, Lost Revenue (this period), Lost Revenue (per year), Checkout Completion Rate, Verdict
**Core formula:** Cart abandonment rate: Abandonment Rate = (Carts Created − Completed Orders) ÷ Carts Created × 100
**Q: What is a cart abandonment calculator?** This calculator finds the share of started checkouts that never become orders and what that costs you. Enter checkouts started, completed orders, and average order value, and it returns your abandonment rate, lost revenue, and realistically recoverable amount — for the period and annualized.
**Q: How do you calculate cart abandonment rate?** Cart abandonment rate = (carts created − completed orders) ÷ carts created × 100. If 1,000 shoppers start a checkout and 300 complete it, 700 carts are abandoned — 700 ÷ 1,000 = 70%. Completion is the flip side: 30% here. The two always sum to 100%.
**Q: What is a good cart abandonment rate?** Baymard Institute's meta-analysis puts the average online rate at ~70%. Below 60% is strong, 60–70% around average, 70–80% high, above 80% very high and usually points to a checkout problem. Rates vary — travel and finance run higher; well-optimised stores can push below 60%.
**Last updated:** 2026-06-07

### Inventory Turnover Calculator
**URL:** https://calcrux.com/tools/ecommerce/inventory-turnover-calculator
**What it does:** Free inventory turnover calculator — ratio, days sales of inventory, weeks of supply, and a benchmark verdict for any period or currency. Calculate free →
**Key outputs:** Inventory Turnover, Days Sales of Inventory (DSI), Weeks of Supply, Months of Supply, Average Inventory (at cost), Verdict
**Core formula:** Inventory turnover ratio: Inventory Turnover = Cost of Goods Sold ÷ Average Inventory (at cost)
**Q: What is inventory turnover and what does it tell you?** Inventory turnover is how many times you sold through your average inventory. A turnover of 6 means you sold and replaced stock six times. It measures velocity — how quickly cash tied up in inventory recycles. High = less cash frozen in stock; low = overstocking or slow movers.
**Q: How do you calculate inventory turnover?** Inventory turnover = COGS ÷ average inventory, both at cost. Average inventory = (beginning + ending) ÷ 2. Example: 1,200,000 in COGS on 200,000 average inventory = 6.0 turns. This calculator does the math and benchmarks the result.
**Q: What is days sales of inventory (DSI)?** DSI (also called DIO) = period days ÷ inventory turnover. For a 365-day year, a turnover of 6 gives about 61 days of stock. It tells you directly how many days of inventory you're holding, making overstocking and stockout risk more concrete than the bare ratio.
**Last updated:** 2026-06-07

### Amazon ACOS Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-acos-calculator
**What it does:** Free Amazon ACOS calculator: compute ACOS, break-even ACOS, target ACOS, and net profit from ads. Enter ad spend, revenue, and gross margin to get started.
**Key outputs:** Your ACOS, Break-even ACOS, ROAS, Net Profit from Ads, Target ACOS, Profit per Dollar of Ad Spend
**Core formula:** ACOS: ACOS = (Ad Spend ÷ Ad Revenue) × 100
**Q: What is Amazon ACOS?** ACOS stands for Advertising Cost of Sales. It is your ad spend divided by ad revenue, expressed as a percentage. An ACOS of 25% means you spent 25 in ads to generate 100 in sales. Amazon shows ACOS in your Ads console — lower is generally better, but what counts as "good" depends on your gross margin.
**Q: What is the ACOS formula?** ACOS = (Ad Spend ÷ Ad Revenue) × 100. For example: 500 spend ÷ 2,000 revenue × 100 = 25% ACOS.
**Q: What is a good ACOS on Amazon?** A "good" ACOS is any number below your gross margin percentage. If your gross margin is 35%, then any ACOS below 35% means ads are profitable. Most experienced sellers target an ACOS of 15–25% in well-established categories. Brand-new products may intentionally run higher ACOS to build rank and reviews.
**Last updated:** 2026-06-07

### Amazon TACoS Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-tacos-calculator
**What it does:** Calculate your Amazon TACoS, halo effect, and organic revenue share in seconds. See if your ad spend is building organic rank or just buying paid sales.
**Key outputs:** TACoS, ACOS, Organic Revenue Share, Ad Halo Effect, Total ROAS, Net Profit (Total)
**Core formula:** Total Revenue: Total Revenue = Ad Revenue + Organic Revenue
**Q: What is Amazon TACoS?** TACoS stands for Total Advertising Cost of Sales. It measures your ad spend as a percentage of your total revenue — both ad-attributed sales and organic sales — for a given period. TACoS = Ad Spend ÷ (Ad Revenue + Organic Revenue) × 100.
**Q: What is the TACoS formula?** TACoS = (Ad Spend ÷ Total Revenue) × 100, where Total Revenue = Ad Revenue + Organic Revenue. For example: 500 ad spend ÷ (2,000 ad revenue + 1,500 organic revenue) × 100 = 14.3% TACoS.
**Q: What is the difference between ACOS and TACoS?** ACOS measures ad spend against ad-attributed revenue only. TACoS measures ad spend against all revenue — paid and organic. TACoS is always ≤ ACOS (because total revenue ≥ ad revenue). The gap between ACOS and TACoS is the halo effect: organic sales your ads helped generate by improving your ranking.
**Last updated:** 2026-06-07

### Amazon Referral Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-referral-fee-calculator
**What it does:** Look up the exact Amazon referral fee for any product category. Covers all 35 categories, tiered rates, and the per-item minimum — updated for 2026.
**Key outputs:** Referral Fee per Unit, Monthly Referral Fees, Category Referral Rate, Net After Referral Fee, Effective Fee Rate
**Core formula:** Standard referral fee: Referral Fee = Selling Price × (Category Rate % ÷ 100)
**Q: What is the Amazon referral fee?** The Amazon referral fee is a percentage of the selling price that Amazon charges as a commission on every sale. It varies by product category — from 8% for consumer electronics to 45% for Amazon device accessories. The fee is deducted from your payout before Amazon deposits funds into your account.
**Q: How is the Amazon referral fee calculated?** Amazon referral fee = Selling Price × Category Rate %, with a minimum fee (usually 0.30) applied if the percentage is lower. For example: a 29.99 Home & Kitchen item at 15% = 4.50 in fees. A 1.00 item at 15% = 0.15, but the 0.30 minimum applies, so the fee is 0.30.
**Q: What is the Amazon referral fee by category?** The most common referral fee is 15%, covering categories like Home & Kitchen, Sports, Toys, Pet Supplies, and most apparel. Electronics, Cameras, and Computers charge 8%. Clothing & Accessories charges 17%. Jewelry and Gift Cards charge 20%. Amazon Device Accessories charge 45%. Some categories (Beauty, Health, Grocery, Baby) have tiered rates: 8% below a price threshold, 15% above it.
**Last updated:** 2026-06-07

### Amazon Storage Fee Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-storage-fee-calculator
**What it does:** Calculate Amazon FBA monthly storage fees by size tier and season, plus long-term storage fees for inventory aged over 365 days. Updated for the 2026 fee schedule.
**Key outputs:** Monthly Storage Fee, Total Storage Cost, Total Cubic Feet, Storage Fee per 1,000 Units, Long-Term Storage Fee
**Core formula:** Cubic feet per unit (from dimensions): Cubic Feet = (Length × Width × Height in inches) ÷ 1,728
**Q: How does Amazon calculate FBA storage fees?** Amazon FBA storage fees are calculated monthly based on the cubic feet of space your inventory occupies: Storage Fee = Cubic Feet per Unit × Number of Units × Monthly Rate per Cubic Foot. The monthly rate depends on the product's size classification (standard or oversize) and the time of year (off-peak Jan–Sep vs. Q4 Oct–Dec).
**Q: What are the Amazon FBA storage fee rates for 2026?** Standard-size products: 0.78/cubic foot per month off-peak (Jan–Sep), 2.40/cubic foot in Q4 (Oct–Dec). Oversize products: 0.56/cubic foot off-peak, 1.40/cubic foot in Q4. These are Amazon's 2026 published rates — verify against Seller Central for the most current figures.
**Q: What is the Amazon long-term storage fee?** Amazon charges a long-term storage fee on inventory that has been at their fulfillment centers for more than 365 days. The fee is the greater of 6.90 per cubic foot or 0.15 per unit, assessed monthly. This is in addition to the regular monthly storage fee.
**Last updated:** 2026-06-07

### Amazon IPI Score Calculator
**URL:** https://calcrux.com/tools/ecommerce/amazon-ipi-score-calculator
**What it does:** Estimate your Amazon IPI score and find out which of the four factors is dragging it below 400. Free IPI calculator — no account required. Directional estimate only.
**Key outputs:** Estimated IPI Score, In-Stock Score, Sell-Through Score, Excess Inventory Penalty, Stranded Inventory Penalty
**Core formula:** In-Stock Score (0–400): In-Stock Score = In-Stock Rate % ÷ 100 × 400
**Q: What is the Amazon IPI score?** The Inventory Performance Index (IPI) is a score Amazon assigns to FBA sellers, ranging from 0 to 1000. It reflects how well you manage your FBA inventory across four factors: in-stock rate, sell-through rate, excess inventory, and stranded inventory. Amazon requires a minimum IPI of 400 — sellers below this threshold face storage limits and restrictions on creating inbound shipments.
**Q: What IPI score do I need to avoid Amazon storage limits?** Amazon requires an IPI score of at least 400 to maintain unrestricted FBA storage. Sellers who fall below 400 face storage limits per storage type (standard-size, oversize, etc.) and may be restricted from sending new inbound shipments until the score improves. Some sellers report informal thresholds for additional benefits above 600 and 750.
**Q: What factors make up the Amazon IPI score?** Amazon discloses four factors that influence IPI: (1) In-stock rate — the percentage of time your products are buyable; (2) Sell-through rate — units sold per unit on hand over 90 days; (3) Excess inventory — the percentage of inventory with more than 90 days of supply; (4) Stranded inventory — inventory stored at Amazon without an active listing. Amazon weights in-stock rate most heavily.
**Last updated:** 2026-06-07

### Cost Per Acquisition (CPA) Calculator
**URL:** https://calcrux.com/tools/ecommerce/cost-per-acquisition-calculator
**What it does:** Free CPA calculator: compute cost per acquisition, break-even CPA, target CPA, and net profit from any ad channel. Works for Google, Meta, Amazon, and more.
**Key outputs:** Cost Per Acquisition (CPA), Break-Even CPA, ROAS, Net Profit on Campaign, Target CPA, CPA vs Target
**Core formula:** Cost Per Acquisition (CPA): CPA = Ad Spend ÷ Conversions
**Q: What is cost per acquisition (CPA)?** Cost per acquisition (CPA) is the total ad spend for a campaign divided by the number of conversions (purchases) it generated. If you spent {{adSpend}} and got {{conversions}} customers, your CPA is {{cpa}}. CPA measures the efficiency of a specific campaign, not your total business acquisition cost (which is CAC).
**Q: What is the CPA formula?** CPA = Ad Spend ÷ Conversions. That is the basic formula. To know whether your CPA is profitable, you also need the break-even CPA: AOV × gross margin %. Your CPA must be below break-even CPA for each customer to generate positive gross profit.
**Q: What is a good CPA for ecommerce?** A good CPA is one below your break-even CPA (AOV × gross margin %). As a rough guide, sustainable ecommerce CPAs are typically 15–30% of AOV for Google Search and 12–20% for Meta, but this varies by margin. A product with a high gross margin can sustain a higher CPA than a low-margin product at the same price.
**Last updated:** 2026-06-07

### Marketing ROI Calculator
**URL:** https://calcrux.com/tools/ecommerce/marketing-roi-calculator
**What it does:** Calculate marketing ROI on gross profit and LTV-adjusted basis, plus break-even spend and net profit. Free ROMI calculator for ecommerce and DTC brands.
**Key outputs:** Marketing ROI, LTV-Adjusted ROI, Net Marketing Profit, Revenue Multiple (ROMI), Gross Margin, Break-Even Marketing Spend
**Core formula:** Gross Profit: Gross Profit = Revenue Attributed − Cost of Goods Sold
**Q: What is marketing ROI?** Marketing ROI (or ROMI — Return on Marketing Investment) is the net profit generated by your marketing spend, divided by that spend. The formula is: Marketing ROI = (Gross Profit − Marketing Spend) ÷ Marketing Spend × 100. A 100% ROI means you doubled your investment; 0% is break-even; negative is a loss.
**Q: What is the marketing ROI formula?** Marketing ROI = (Gross Profit − Marketing Spend) ÷ Marketing Spend × 100. Gross Profit = Revenue Attributed − Cost of Goods. Many guides use revenue instead of gross profit — this overstates ROI significantly because it ignores product cost.
**Q: What is a good marketing ROI for ecommerce?** Most scaling ecommerce brands target 200–500% marketing ROI (meaning you get 2–5× your spend back in profit). Below 100% means each marketing dollar generates less than a dollar of profit. Email typically achieves 2000%+; paid social runs 100–300%; paid search 200–400%. The right benchmark depends on your channel mix and margin.
**Last updated:** 2026-06-07

### Marketing Efficiency Ratio (MER) Calculator
**URL:** https://calcrux.com/tools/ecommerce/marketing-efficiency-ratio-calculator
**What it does:** Calculate your blended MER (total revenue / total ad spend) across all channels. Find break-even MER, net profit, and channel concentration risk. Free tool.
**Key outputs:** Marketing Efficiency Ratio (MER), Break-Even MER, Net Marketing Profit, Ad Spend as % of Revenue, Channel Concentration
**Core formula:** Marketing Efficiency Ratio (MER): MER = Total Revenue ÷ Total Ad Spend
**Q: What is Marketing Efficiency Ratio (MER)?** MER is total store revenue divided by total ad spend across all channels — the blended ROAS at the business level. It bypasses per-channel attribution by using actual bank revenue vs actual total spend. At {{totalRevenue}} revenue and {{totalAdSpend}} spend, MER = {{mer}}.
**Q: What is the MER formula?** MER = Total Revenue ÷ Total Ad Spend. Simple division — no attribution model needed. A MER of 5 means every dollar of ad spend generated five dollars of total revenue.
**Q: What is a good MER for ecommerce?** The answer depends on your gross margin. Break-even MER = 1 ÷ gross margin. At 40% margin, break-even is 2.5×. A healthy DTC brand typically targets 3–6× MER. Amazon-heavy brands often run 2–4×. Omnichannel brands with strong organic may achieve 5–8×.
**Last updated:** 2026-06-07

### Customer Payback Period Calculator
**URL:** https://calcrux.com/tools/ecommerce/customer-payback-period-calculator
**What it does:** Calculate months to recover CAC from gross profit. Includes LTV:CAC ratio, 12-month LTV, and break-even insights. Free customer payback period calculator.
**Key outputs:** Payback Period (months), 12-Month LTV:CAC Ratio, Monthly Gross Margin per Customer, 12-Month Customer LTV, Payback Period (years), 24-Month Customer LTV
**Core formula:** Monthly gross margin per customer: Monthly Gross Margin = AOV × (Purchases/Year ÷ 12) × Gross Margin %
**Q: What is customer payback period?** Customer payback period is the number of months it takes for the gross profit generated by a customer to fully recover the customer acquisition cost (CAC). If CAC is {{cac}} and the customer generates {{grossMarginPerCustomerPerMonth}} in gross profit per month, payback = {{paybackMonths}} months.
**Q: What is the payback period formula?** Payback (months) = CAC ÷ Monthly Gross Margin per Customer. Monthly Gross Margin = AOV × (Purchases/Year ÷ 12) × Gross Margin %. The formula uses gross profit, not revenue, so it reflects the cash actually available to recover acquisition cost.
**Q: What is a good customer payback period?** Under 6 months is excellent for ecommerce. 6–12 months is acceptable. Over 12 months strains cash flow and limits how aggressively you can scale. Subscription brands typically achieve 1–3 months; low-frequency or luxury brands may run 12–24 months by necessity.
**Last updated:** 2026-06-07

### Contribution Margin Calculator
**URL:** https://calcrux.com/tools/ecommerce/contribution-margin-calculator
**What it does:** Calculate contribution margin per unit, CM ratio, break-even units, and margin of safety. Free contribution margin calculator — all variable costs included.
**Key outputs:** Contribution Margin per Unit, Contribution Margin Ratio (CMR), Break-Even Units, Monthly Net Profit, Margin of Safety, Operating Leverage
**Core formula:** Variable Cost per Unit: Variable Cost = COGS + Shipping + Marketplace Fee + Return Cost + Ad Spend
**Q: What is contribution margin?** Contribution margin is the selling price minus all variable costs per unit. It is the amount each unit sold contributes toward covering fixed costs and, once those are covered, profit. At a {{sellingPrice}} selling price and {{variableCostPerUnit}} in variable costs, contribution margin = {{contributionMarginPerUnit}} per unit.
**Q: What is the contribution margin formula?** Contribution Margin = Selling Price − Variable Costs. Variable costs include COGS, shipping, marketplace fees, amortized returns, and per-unit ad spend. CM Ratio = Contribution Margin ÷ Selling Price × 100.
**Q: What is a good contribution margin ratio?** It depends heavily on the product category. Electronics typically run 10–35%; beauty and personal care 35–55%; apparel 30–50%. For ecommerce, most products need at least 20% CMR to cover fixed costs at realistic volumes. Below 15% is thin and requires high volume to break even.
**Last updated:** 2026-06-07

### Inventory Forecast Calculator
**URL:** https://calcrux.com/tools/ecommerce/inventory-forecast-calculator
**What it does:** Project demand for 30–90 days with growth trend and seasonal adjustment. Get reorder point, safety stock, and order quantity instantly. Free forecast calculator
**Key outputs:** Forecasted Demand, Recommended Order Quantity, Reorder Point, Stockout Risk, Days Until Reorder
**Core formula:** Growth multiplier (compound): Growth Multiplier = (1 + Monthly Growth Rate ÷ 100) ^ (Forecast Days ÷ 30)
**Q: What is an inventory forecast calculator?** An inventory forecast calculator projects how many units you will sell over a future period — typically 30 to 90 days — by combining your historical daily sales rate with an expected growth trend and seasonal adjustment. It then calculates safety stock, reorder point, and recommended order quantity so you know exactly how much to buy.
**Q: How do you calculate demand forecast for inventory?** Demand forecast = avg daily sales × growth multiplier × seasonal factor × forecast days. The growth multiplier compounds your monthly growth rate over the period: (1 + monthly rate)^(months). For example, 10% monthly growth over 90 days = (1.10)³ = 1.331 — a 33% uplift on the baseline daily rate.
**Q: What is safety stock and how much should I carry?** Safety stock is the inventory buffer you hold above the lead time demand to absorb demand spikes and supplier delays. A simple rule: safety stock = average daily sales × safety days. For low-variability products with a 30-day lead time, 14 safety days is a typical starting point. High-variability products or unreliable suppliers warrant 20–30+ safety days.
**Last updated:** 2026-06-07

### Reorder Point Calculator
**URL:** https://calcrux.com/tools/ecommerce/reorder-point-calculator
**What it does:** Calculate the exact inventory level to trigger your next order using the ROP formula. Includes safety stock, days-until-reorder, and stockout risk alert. Free.
**Key outputs:** Reorder Point, Safety Stock, Lead Time Demand, Days Until Reorder, Days of Coverage at ROP, Stock on Arrival
**Core formula:** Lead time demand: Lead Time Demand = Average Daily Sales × Lead Time Days
**Q: What is a reorder point?** The reorder point (ROP) is the inventory level at which you must place a new purchase order to avoid running out of stock before the next shipment arrives. It equals lead time demand (units sold during the lead time at average rate) plus safety stock (a buffer for demand spikes).
**Q: How do you calculate the reorder point?** Reorder Point = (Average Daily Sales × Lead Time Days) + Safety Stock. Safety Stock = (Maximum Daily Sales − Average Daily Sales) × Lead Time Days. For example, if you sell 10 units/day on average (15 max) with a 30-day lead time: ROP = (10 × 30) + (15 − 10) × 30 = 300 + 150 = 450 units.
**Q: What is safety stock in the reorder point formula?** Safety stock is the buffer inventory above average lead time demand that protects against demand spikes during the lead time. It is calculated as (max daily sales − average daily sales) × lead time days. Without safety stock, any week that runs above average during the lead time can cause a stockout.
**Last updated:** 2026-06-07

### Inventory Carrying Cost Calculator
**URL:** https://calcrux.com/tools/ecommerce/inventory-carrying-cost-calculator
**What it does:** Calculate the true annual cost of holding stock: capital, storage, insurance, shrinkage, and obsolescence. Get per-unit holding cost instantly. Free tool.
**Key outputs:** Annual Carrying Cost, Total Carrying Cost Rate, Monthly Carrying Cost, Annual Cost per Unit, Weekly Carrying Cost, Carrying Cost as Turns
**Core formula:** Total carrying cost rate: Total Rate = Capital Cost % + Storage % + Insurance % + Shrinkage % + Obsolescence % + Handling %
**Q: What is inventory carrying cost?** Inventory carrying cost (also called holding cost) is the total annual expense of keeping inventory on hand. It includes the opportunity cost of capital tied up in stock, warehousing fees, insurance, shrinkage (theft/damage), obsolescence, and handling overhead. For most ecommerce businesses it runs 20–35% of inventory value per year.
**Q: How do you calculate inventory carrying cost?** Annual Carrying Cost = Average Inventory Value × Total Carrying Cost Rate. The total rate is the sum of all cost components (capital + storage + insurance + shrinkage + obsolescence + handling) expressed as annual percentages of inventory value. For example: 50,000 inventory value × 22% = 11,000 per year.
**Q: What is a typical inventory carrying cost rate?** Most ecommerce and retail businesses have a carrying cost rate of 20–35% per year. Manufacturing businesses tend to run 15–25%. Very high-obsolescence categories (fashion, electronics, perishables) can run 35–50%+. The most commonly underestimated component is capital cost, which alone is typically 10–15%.
**Last updated:** 2026-06-07

### Stock Coverage Calculator
**URL:** https://calcrux.com/tools/ecommerce/stock-coverage-calculator
**What it does:** Calculate days of stock coverage, whether you face a stockout or overstock, and the revenue at risk. Free stock coverage calculator with instant DOH analysis.
**Key outputs:** Days of Stock Coverage, Weeks of Coverage, Revenue at Risk, Units Shortfall vs Target, Excess Inventory Value, Ideal Stock Level
**Core formula:** Days of stock coverage: Days of Coverage = Current Stock ÷ Average Daily Sales
**Q: What is stock coverage and how do you calculate it?** Stock coverage (days of inventory on hand) measures how long your current stock will last at the current average daily sales rate. The formula is: Days of Coverage = Current Stock ÷ Average Daily Sales. For example, 500 units at 10 units per day = 50 days of coverage.
**Q: What is a good number of days of stock coverage?** Good coverage = at least 1.5× your supplier lead time, minimum. For overseas-sourced products (30–45-day lead time), 60–90 days is typical. For domestic-sourced products, 30–60 days. The hard rule: coverage must always exceed your lead time or you face a stockout.
**Q: When is stockout risk flagged by this calculator?** Stockout risk is flagged when your days of coverage are less than your lead time. This means you will run out of stock before the next order arrives. The calculator also quantifies the revenue at risk — the sales you will miss during the stockout window.
**Last updated:** 2026-06-09

### Dead Stock Calculator
**URL:** https://calcrux.com/tools/ecommerce/dead-stock-calculator
**What it does:** Quantify dead stock carrying costs and get a data-driven recommendation: liquidate, discount, or hold. Includes break-even analysis and monthly cost. Free tool.
**Key outputs:** Dead Stock Value (at cost), Monthly Carrying Cost, Recommended Action, Liquidation Recovery, Profit at Clearance Price, Break-even (liquidation vs holding)
**Core formula:** Dead stock value and monthly cost: Dead Stock Value = Dead Units × Cost Per Unit  |  Monthly Cost = Dead Stock Value × Monthly Carrying Rate ÷ 100
**Q: What is dead stock?** Dead stock (also called dead inventory or non-moving stock) is inventory that has stopped selling and is unlikely to clear at the original price. It ties up capital, consumes carrying costs, and takes up warehouse space that could be used for faster-moving products.
**Q: How do you calculate the cost of dead stock?** Dead stock value = units × cost per unit. Monthly carrying cost = dead stock value × monthly carrying rate. Total cost incurred = monthly cost × months stagnant. For example: 100 units × 25 cost per unit = 2,500 in value. 2,500 × 2% monthly rate = 50/month, 300 incurred after 6 months.
**Q: When should I liquidate dead stock vs try to sell it at a discount?** Discount if you can still make a profit — discounted revenue > cost is the test. If discounting is not profitable, compare the liquidation loss against future monthly carrying costs: if the carrying cost catches up to the liquidation loss within 6 months (break-even ≤ 6), liquidate. If not, holding may be rational while you try other clearance options.
**Last updated:** 2026-06-09

### Product Profitability Calculator
**URL:** https://calcrux.com/tools/ecommerce/product-profitability-calculator
**What it does:** Free product profitability calculator: compute net profit per unit, margin, ROI, and monthly projections — platform fees, fulfillment, ad spend, and returns included.
**Key outputs:** Net Profit / Unit, Net Margin, Monthly Net Profit, Gross Profit / Unit, Gross Margin, ROI on Cost, Break-even Units / Month, Total Variable Cost / Unit
**Core formula:** Platform fee amount: Platform Fee Amount = Selling Price × Platform Fee % ÷ 100
**Q: How do I calculate product profitability?** Product profitability = selling price minus all variable costs per unit: COGS, marketplace fee, fulfillment, ad spend per unit, and return costs. Divide by selling price to get net margin. This calculator does all of it in one step — enter your numbers and see the result instantly.
**Q: What costs should I include in per-unit profitability?** Include every cost that scales with each unit sold: product cost (COGS), platform referral or transaction fee, fulfillment cost (FBA, shipping, or 3PL), ad spend per unit (total monthly ad spend divided by units sold), and return costs amortised across all units. Fixed costs like software subscriptions are excluded from per-unit profit and appear only in the break-even calculation.
**Q: What is a good net margin per unit for ecommerce?** For most ecommerce products, 15–25% net margin per unit is considered healthy. Under 10% is thin — a small cost increase can flip it to a loss. Over 25% is strong and gives room to scale ad spend. Margins vary by category: commodities run 5–15%, premium or private-label brands often 20–35%.
**Last updated:** 2026-06-09

### Ecommerce Unit Economics Calculator
**URL:** https://calcrux.com/tools/ecommerce/ecommerce-unit-economics-calculator
**What it does:** Calculate contribution margin, break-even units per month, and monthly P&L from variable and fixed costs. Free ecommerce unit economics calculator — any currency.
**Key outputs:** Contribution Margin / Unit, Contribution Margin Ratio, Monthly Net Profit, Variable Cost / Unit, Break-even Units / Month, Monthly Revenue, Revenue to Break-even
**Core formula:** Variable cost per unit: Variable Cost / Unit = COGS + (Selling Price × Platform Fee %) + Fulfillment + Ad Spend / Unit
**Q: What is contribution margin in ecommerce?** Contribution margin is selling price minus all variable costs per unit — COGS, platform fee, fulfillment, and ad spend. It represents how much each unit sold contributes toward covering your fixed overheads and generating profit. If CM is negative, every unit sold deepens the loss regardless of volume.
**Q: How do I calculate break-even units per month?** Break-even units = fixed monthly costs ÷ contribution margin per unit, rounded up to the nearest whole unit. For example, 800 in fixed costs with a 16.25 CM per unit gives a break-even of 50 units per month (800 ÷ 16.25 = 49.2, rounded up to 50).
**Q: What is the difference between contribution margin and gross margin?** Gross margin subtracts only COGS from selling price. Contribution margin subtracts all variable costs — COGS plus platform fees, fulfillment, and ad spend. Contribution margin is a lower number than gross margin but a more accurate picture of what each unit actually earns after every per-unit cost.
**Last updated:** 2026-06-09

### Customer Retention Rate Calculator
**URL:** https://calcrux.com/tools/ecommerce/customer-retention-rate-calculator
**What it does:** Calculate customer retention rate, churn rate, customer lifespan, LTV, and the revenue impact of a 1% retention improvement. Free customer retention calculator.
**Key outputs:** Customer Retention Rate, Customer Churn Rate, Customer LTV, Avg Customer Lifespan (months), Monthly Churn Revenue Loss, 1% Retention Improvement Value
**Core formula:** Retained customers: Retained Customers = End Customers − New Customers
**Q: How do you calculate customer retention rate?** Customer Retention Rate = ((End Customers − New Customers) ÷ Start Customers) × 100. First subtract new customers acquired during the period from the end-period count to get retained customers — those who were there at the start AND the end. Then divide by starting customers. A business that starts with 1,000 customers, acquires 200 new ones, and ends with 850 has retained 650 original customers: 65% retention rate.
**Q: What is a good customer retention rate for ecommerce?** For ecommerce, 75–85% annual retention is considered good and 85%+ is excellent. Below 60% is a danger zone — the business is losing more than 40% of its customers each year, which makes growth extremely difficult as acquisition must replace losses before any net growth occurs. Subscription businesses typically retain 85%+ to be viable.
**Q: What is the difference between retention rate and churn rate?** They are complements that add to 100%: retention rate + churn rate = 100%. Retention rate measures the customers you kept; churn rate measures the customers you lost. A 70% retention rate means a 30% churn rate. Both describe the same data — churn is often used for subscriptions and SaaS, retention is more common in ecommerce and DTC.
**Last updated:** 2026-06-09

### Revenue Projection Calculator
**URL:** https://calcrux.com/tools/ecommerce/revenue-projection-calculator
**What it does:** Project 3–24 months of revenue using compound growth, seasonality, and gross margin. Get cumulative revenue, annualised run rate, and gross profit. Free tool.
**Key outputs:** Projected Revenue (End of Period), Cumulative Revenue, Annualized Run Rate, Total Growth over Period, Projected Gross Profit (Cumulative), Implied Monthly Growth Rate
**Core formula:** Monthly growth rate from annual: Monthly Growth Rate = (1 + Annual Growth Rate)^(1/12) − 1
**Q: How do you calculate revenue projections?** Revenue projections use compound monthly growth: Revenue[month M] = Current Monthly Revenue × (1 + monthly growth rate)^M × seasonality factor. The monthly growth rate is derived from the annual rate as (1 + annual rate)^(1/12) − 1. Sum all monthly projections for cumulative revenue. This calculator does all the math automatically — enter your current revenue and growth rate and read the result.
**Q: What is the difference between linear and compound revenue growth?** Linear growth adds the same fixed amount every month (e.g. +2,500 per month). Compound growth multiplies by the same rate every month, so each month's starting point is larger than the last. Over 12+ months the difference is significant. A business growing at 30% annually is growing at 2.21% monthly (compound) — not 2.5% per month (linear/÷12). Always use compound growth for revenue projections.
**Q: What is annualised run rate and how is it calculated?** Annualised run rate (ARR) is your end-of-period monthly revenue multiplied by 12. If your projected monthly revenue at month 12 is 32,500, the ARR is 390,000. It represents implied annual revenue if the business stayed at that monthly level. ARR is used by investors and acquirers to benchmark and value businesses — it's different from last year's actual revenue.
**Last updated:** 2026-06-09

### Ad Spend Scaling Simulator
**URL:** https://calcrux.com/tools/ecommerce/ad-spend-scaling-simulator
**What it does:** Simulate profit, ROAS, and marginal return of scaling your ad budget. Model constant ROAS or realistic diminishing returns. Free ad spend scaling simulator.
**Key outputs:** Projected Monthly Profit, Projected ROAS, Incremental Profit, Projected Total Revenue, Marginal ROAS, Break-even Ad Spend, Projected TACoS
**Core formula:** Constant ROAS model: Projected ROAS = Current ROAS (unchanged)
**Q: What is marginal ROAS and why does it matter?** Marginal ROAS is the ROAS on the incremental spend only — the extra revenue per extra dollar of budget. If you spend 3,000 at 3.5 ROAS then add 3,000 more, overall ROAS may look fine at 3.2 while the marginal ROAS on the extra 3,000 is only 2.1. When it drops below 1.0, the extra spend loses money.
**Q: How does the diminishing returns model work?** Projected ROAS = Current ROAS × (Current Spend ÷ Target Spend)^0.25. The 0.25 exponent is the industry benchmark for paid search/social — doubling spend cuts ROAS by roughly 16% (0.5^0.25 = 0.841). Constant ROAS is the optimistic ceiling; this model is the realistic default for most campaigns.
**Q: What is break-even ad spend?** Break-even ad spend is the maximum monthly budget where profit = 0. Formula: (Fixed Costs − Organic Revenue × Margin) ÷ (ROAS × Margin − 1). If organic revenue already covers fixed costs, the result is zero — ads only need to pay for themselves at that point.
**Last updated:** 2026-06-09

---

## Ecosystem 2 — India Business Operations

HR, salary, GST, and business finance tools for Indian businesses

### In-Hand Salary Calculator
**URL:** https://calcrux.com/tools/india-business/in-hand-salary-calculator
**What it does:** Free in-hand salary calculator for India — CTC to monthly take-home, old vs new tax regime, HRA, EPF, and professional tax, FY 2026-27. Calculate free →
**Key outputs:** Monthly Take-Home, Annual Take-Home, Effective Tax Rate, Income Tax / Month, PF Deduction / Month, Professional Tax / Month, HRA Exemption (Annual), Annual Taxable Income, Savings vs Other Regime
**Core formula:** Gross Salary: Gross Salary = CTC − Employer PF − Gratuity Provision
**Region:** IN only (INR)
**Q: What is CTC and how is it different from in-hand salary?** CTC is everything the employer spends — basic salary, allowances, employer PF (12% of basic), and gratuity. In-hand is what reaches your account after income tax, PF, and professional tax are deducted. A 10 lakh CTC typically yields 7–8.5 lakh take-home depending on regime and deductions.
**Q: How do I choose between the old and new tax regime?** The new regime has lower slab rates but no exemptions. The old regime lets you claim HRA, 80C (up to ₹1.5L), 80D, and more. If total deductions exceed ₹3–4 lakh, old regime often wins. For fewer deductions or simplicity, new regime is usually better. Compare both here instantly.
**Q: How is HRA exemption calculated?** HRA exemption (old regime only) is the minimum of: (1) Actual HRA received, (2) 50% of basic for metro / 40% for non-metro, and (3) Annual rent paid minus 10% of basic. All three must be positive for any exemption to apply. Under the new regime, HRA exemption is not available at all.
**Last updated:** 2026-06-09

### Income Tax Calculator India
**URL:** https://calcrux.com/tools/india-business/income-tax-calculator
**What it does:** Free income tax calculator India — exact tax under old vs new regime, 80C and 80D deductions, surcharge, and 87A rebate for FY 2025-26. Calculate free →
**Key outputs:** Total Tax Payable, Effective Tax Rate, Savings vs Other Regime, Taxable Income, Base Income Tax, Surcharge, Health & Education Cess, Tax Remaining After TDS, Recommended Regime
**Core formula:** Taxable Income: Taxable Income = Gross Income − Standard Deduction − Eligible Deductions
**Region:** IN only (INR)
**Q: What is the new tax regime for FY 2025-26?** The new tax regime (Budget 2025, effective FY 2025-26) has seven slabs: 0% up to ₹4 lakh, 5% from ₹4–8 lakh, 10% from ₹8–12 lakh, 15% from ₹12–16 lakh, 20% from ₹16–20 lakh, 25% from ₹20–24 lakh, and 30% above ₹24 lakh. It also includes a ₹75,000 standard deduction. With these revised slabs, tax on ₹12 lakh taxable income = exactly ₹60,000, which is fully wiped by the Section 87A rebate. This means anyone earning up to ₹12.75 lakh gross (₹12L after ₹75K standard deduction) pays zero income tax. It is the default regime from FY 2023-24 and cannot claim most exemptions or deductions.
**Q: Who should choose the old tax regime over the new one?** The old regime is better when your total eligible deductions are large enough to bring your taxable income significantly lower than what the new regime would compute. As a rule of thumb: if you can claim more than ₹3–4 lakh in combined deductions (80C ₹1.5L + NPS ₹50K + HRA + 80D + home loan interest), the old regime often wins. If you have minimal deductions or want simplicity, the new regime is usually better. Use this calculator to run both and compare instantly — the "Savings vs Other Regime" card tells you exactly which one is better for your numbers.
**Q: What is the Section 87A rebate and how does it work?** Section 87A is a tax rebate that reduces your final tax liability — or wipes it out entirely. Under the new regime for FY 2025-26, if your taxable income (after standard deduction) is ₹12 lakh or below, you get a full rebate up to ₹60,000. This means your income tax is zero even if slabs produce some tax. Under the old regime, the rebate is up to ₹12,500 for taxable income ≤ ₹5 lakh. Super senior citizens (80+) are not eligible for the 87A rebate in the old regime. The rebate applies before cess — so cess is charged on the post-rebate tax, not the pre-rebate amount.
**Last updated:** 2026-06-07

### HRA Calculator
**URL:** https://calcrux.com/tools/india-business/hra-calculator
**What it does:** Free HRA calculator India — HRA exemption under Rule 2A, metro vs non-metro rate, three-rule breakdown, and tax saving for FY 2025-26. Calculate free →
**Key outputs:** Annual HRA Exemption, Taxable HRA, Estimated Annual Tax Saving, Rule 1: Actual HRA Received, Rule 2: 50% / 40% of Basic + DA, Rule 3: Rent Paid − 10% of Basic + DA, Binding Constraint (Minimum Rule), Monthly HRA Exemption
**Core formula:** HRA Exemption (Rule 2A): HRA Exempt = min(Rule 1, Rule 2, Rule 3)
**Region:** IN only (INR)
**Q: What is HRA exemption and how does it save tax?** HRA (House Rent Allowance) exemption is a provision under Section 10(13A) of the Income Tax Act that allows salaried employees paying rent to exclude a portion of their HRA from taxable income. The exempt amount is the minimum of three rule-based limits — which means you save tax on that portion. For example, if ₹1,32,000 of your HRA is exempt and you are in the 20% slab, you save approximately ₹27,456 in income tax (20% slab rate plus 4% cess). The exemption is only available under the old tax regime.
**Q: How is HRA exemption calculated?** HRA exemption under Rule 2A is the minimum of: (1) Actual HRA received from your employer, (2) 50% of (Basic Salary + DA) if you live in Delhi, Mumbai, Chennai, or Kolkata, or 40% for any other city, and (3) Annual rent paid minus 10% of (Basic Salary + DA). All three values must be positive for any exemption to apply. If rule 3 turns negative (your rent is less than 10% of your salary base), the entire exemption becomes nil.
**Q: Which cities are treated as "metro" for HRA purposes?** Only four cities are classified as metro under the Income Tax Act for HRA calculation: Delhi, Mumbai, Chennai, and Kolkata. These cities qualify for the higher 50% rate in Rule 2. Bangalore, Hyderabad, Pune, Ahmedabad, and other large cities are NOT metro for HRA purposes — residents there get the 40% non-metro rate, even though these are major business hubs.
**Last updated:** 2026-06-07

### EPF Calculator
**URL:** https://calcrux.com/tools/india-business/epf-calculator
**What it does:** Free EPF calculator India — project your EPF corpus, total interest earned, EPS monthly pension, and VPF impact at retirement for FY 2025-26. Calculate free →
**Key outputs:** EPF Corpus at Retirement, Total Interest Earned, Estimated Monthly Pension, Total Employee Contributions, Total Employer Contributions, Years to Retirement, Corpus Multiple, Final Year Monthly Contribution
**Core formula:** Monthly EPF Contribution: Employee = 12% × Basic | Employer EPF = (12% × Basic) − EPS
**Region:** IN only (INR)
**Q: What is EPF and how does it work?** EPF (Employee Provident Fund) is a retirement savings scheme mandated under the Employees Provident Funds and Miscellaneous Provisions Act, 1952 for establishments with 20 or more employees. Every month, 12% of your basic salary is deducted as your EPF contribution, and your employer matches it with another 12%. Of the employer's 12%, up to ₹1,250/month goes to EPS (Employee Pension Scheme) and the remaining goes to your EPF account. Both your share and the employer's EPF share earn interest at the EPFO-declared annual rate (8.25% for FY 2023-24), which compounds year after year until you retire.
**Q: What is the current EPF interest rate?** The EPFO declared an interest rate of 8.25% per annum for FY 2024-25 — confirmed by the Central Government in May 2025. The rate has ranged from 8.1% to 8.65% over the last decade. It is announced after the EPFO's Central Board of Trustees meeting and credited to EPF accounts at the end of March each year. This calculator uses 8.25% as the default, but you can adjust it for any future change.
**Q: How is EPF corpus calculated?** EPF corpus grows year by year: each year's combined contributions (employee 12% + employer's EPF share) are added to the existing balance, and the whole sum earns interest at the annual EPF rate. This repeats every year until retirement. Because salary typically grows with annual increments, contributions rise each year, and the interest compounds on a larger and larger base — producing substantial corpus over a 25–30 year career. This calculator models that year-by-year growth precisely.
**Last updated:** 2026-06-07

### Freelancer Tax Calculator
**URL:** https://calcrux.com/tools/india-business/freelancer-tax-calculator
**What it does:** Free freelancer tax calculator India — Section 44ADA presumptive income, advance tax by 15 March, GST estimate, and audit check for FY 2025-26. Calculate free →
**Key outputs:** Total Tax Payable, Advance Tax Due (by 15 Mar), Effective Tax Rate, Deemed Taxable Income (50%), Taxable Income (after deductions), Estimated GST to Collect, Tax Balance After TDS, Applicable Receipt Limit, Audit Required?
**Core formula:** Presumptive Income: Presumptive Income = Gross Receipts × 50%
**Region:** IN only (INR)
**Q: What is Section 44ADA?** Section 44ADA is a presumptive taxation scheme for professionals under the Income Tax Act, 1961. It allows eligible professionals — like doctors, lawyers, engineers, architects, CAs, and tech consultants — to declare 50% of their gross professional receipts as taxable income without maintaining detailed books of accounts. The scheme is available to individuals and Hindu Undivided Families (HUFs) whose gross receipts do not exceed ₹75 lakh (if ≥50% receipts are digital) or ₹50 lakh (otherwise) in a financial year.
**Q: Who can use Section 44ADA?** Section 44ADA applies to specified professionals: doctors, lawyers, chartered accountants, architects, engineers, interior decorators, technical consultants, film artists, authorised representatives, and company secretaries. Freelancers working in IT, software development, graphic design, consulting, or legal services typically qualify. The scheme is for individuals and HUFs only — companies, LLPs, and partnership firms cannot opt in. Annual gross receipts must be within the applicable limit (₹75L or ₹50L based on digital transactions).
**Q: What is presumptive income under 44ADA?** Under Section 44ADA, 50% of your gross professional receipts is treated as your taxable income by default. So if you earned ₹18 lakh from clients, your presumptive taxable income is ₹9 lakh. You can declare more than 50% if your actual income is higher, but you cannot declare less than 50%. This eliminates the need to maintain books of accounts, get your accounts audited, or submit expense proofs — a huge simplification for freelancers and self-employed professionals.
**Last updated:** 2026-06-07

### GST Calculator
**URL:** https://calcrux.com/tools/india-business/gst-calculator
**What it does:** Free GST calculator with current 2026 rates (GST 2.0). Add or remove GST, split CGST, SGST and IGST, and apply compensation cess. Calculate GST online free →
**Key outputs:** Taxable Value, Total GST, Total Invoice Value, CGST, SGST / UTGST, IGST, Compensation Cess, Net GST Payable, Effective Tax Rate, GST Rate Applied
**Core formula:** Add GST (exclusive price): GST = Amount × Rate ÷ 100   ·   Total = Amount + GST + Cess
**Region:** IN only (INR)
**Q: What is a GST calculator?** A GST calculator works out the Goods and Services Tax on any amount in India. Enter a price, pick a GST rate (5%, 18%, 40%, etc.), and it shows the GST amount, the CGST/SGST or IGST split, and the total invoice value. It also works in reverse — remove GST from a GST-inclusive price to find the base value.
**Q: How do I calculate GST on an amount?** To add GST: GST = amount × rate ÷ 100, and total = amount + GST. For example, 18% GST on ₹10,000 is ₹1,800, so the total is ₹11,800. To remove GST from a GST-inclusive price: base value = amount ÷ (1 + rate ÷ 100). This calculator does both automatically — just choose "add GST" or "remove GST".
**Q: How do I calculate reverse GST (remove GST from a total)?** Reverse GST extracts the base price and tax from a GST-inclusive amount. The formula is: taxable value = total ÷ (1 + GST rate ÷ 100). For a ₹11,800 GST-inclusive price at 18%, the base value is ₹11,800 ÷ 1.18 = ₹10,000 and the GST is ₹1,800. Select "GST-inclusive — remove GST" as the amount type to do this.
**Last updated:** 2026-06-10

### Gratuity Calculator
**URL:** https://calcrux.com/tools/india-business/gratuity-calculator
**What it does:** Free gratuity calculator for India — compute gratuity under the Payment of Gratuity Act, check 5-year eligibility, and see your tax-free amount. Calculate free →
**Key outputs:** Gratuity Amount, Tax-Free Amount, Taxable Amount, Years Counted, Eligibility, Statutory Max Gratuity
**Core formula:** Covered employer (under the Act): Gratuity = (15 × Last-Drawn Salary × Years) ÷ 26
**Region:** IN only (INR)
**Q: What is a gratuity calculator?** A gratuity calculator works out the lump-sum gratuity an employee receives for long service in India. Enter your last-drawn salary (Basic + DA) and years of service, and it applies the Payment of Gratuity Act formula, checks your eligibility, and shows how much of the amount is tax-free.
**Q: How is gratuity calculated in India?** Gratuity = (15 × last-drawn monthly salary × years of service) ÷ 26 for employers covered by the Act. The salary is Basic + DA only. For example, at ₹60,000 salary and 10 years, gratuity = 15 × 60,000 × 10 ÷ 26 = ₹3,46,154.
**Q: What is the gratuity formula for covered vs non-covered employers?** Covered employers (10+ employees) use 15 days’ salary per year on a 26-day month: (15 × salary × years) ÷ 26. Non-covered employers use a 30-day month: (15 × salary × years) ÷ 30, which is about 13% lower, and count only fully completed years.
**Last updated:** 2026-06-10

### TDS Calculator
**URL:** https://calcrux.com/tools/india-business/tds-calculator
**What it does:** Free TDS calculator for India — pick the section (194C, 194J, 194I rent, interest), enter the amount, and get the TDS rate, amount, and net payment. FY 2025-26.
**Key outputs:** TDS Amount, Net Payment, TDS Rate Applied, Annual Threshold, Threshold Status, Section
**Core formula:** TDS amount: TDS = Amount × Rate ÷ 100   (only if Amount > Threshold)
**Region:** IN only (INR)
**Q: What is a TDS calculator?** A TDS calculator works out the Tax Deducted at Source on a payment in India. Pick the payment type (the TDS section), enter the amount, and it returns the correct rate, the TDS to deduct, and the net amount the payee receives — using the current FY 2025-26 rates and thresholds.
**Q: How is TDS calculated?** TDS = payment amount × the section rate, but only once the annual payment crosses that section's threshold. For example, professional fees of ₹1,00,000 under Section 194J (10%, threshold ₹50,000) means TDS of ₹10,000 and a net payment of ₹90,000.
**Q: What are the TDS rates for FY 2025-26?** Common rates: 194J professional fees 10% (technical 2%), 194C contractor 1% (individual) or 2% (company), 194I rent 10% (building) or 2% (plant), 194H commission 2%, 194A interest 10%, 194T partner remuneration 10%, and 194Q/194O 0.1%. Each has its own threshold.
**Last updated:** 2026-06-10

### Advance Tax Calculator
**URL:** https://calcrux.com/tools/india-business/advance-tax-calculator
**What it does:** Free advance tax calculator for India — find your advance tax after TDS, the four instalment amounts, and due dates (15 Jun/Sep/Dec/Mar). FY 2025-26 →
**Key outputs:** Advance Tax Payable, Balance to Pay, Liability, Due by 15 Jun (15%), Due by 15 Sep (45%), Due by 15 Dec (75%), Due by 15 Mar (100%), 234C Interest, 234B Interest, Total Interest
**Core formula:** Advance tax payable: Advance Tax = Estimated Annual Tax − TDS   (if ≥ ₹10,000)
**Region:** IN only (INR)
**Q: What is advance tax?** Advance tax is income tax you pay during the year — as you earn — instead of in one lump sum at the end. Anyone whose tax for the year, after TDS, is ₹10,000 or more must pay it in instalments by fixed due dates, or face interest under Sections 234B and 234C.
**Q: Who has to pay advance tax?** Anyone whose net tax liability for the year (after TDS) is ₹10,000 or more — salaried people with extra income, freelancers, professionals, businesses, and investors. Senior citizens (60+) with no business income are exempt and can pay at the time of filing.
**Q: What are the advance tax due dates for FY 2025-26?** Four instalments: 15% by 15 June, 45% (cumulative) by 15 September, 75% by 15 December, and 100% by 15 March. Presumptive taxpayers under 44AD/44ADA pay the full 100% in a single instalment by 15 March.
**Last updated:** 2026-06-10

### Professional Tax Calculator
**URL:** https://calcrux.com/tools/india-business/professional-tax-calculator
**What it does:** Free professional tax calculator for India — find the PT deducted from your salary by state (Maharashtra, Karnataka, WB, TN), monthly and yearly. FY 2025-26.
**Key outputs:** Annual Professional Tax, Monthly Professional Tax, Applicability, Statutory Maximum
**Core formula:** State slab lookup: Annual PT = slab amount for (gross salary, state) — capped at ₹2,500
**Region:** IN only (INR)
**Q: What is professional tax?** Professional tax is a small tax that state governments levy on salaried employees and professionals — the "PT" line on your salary slip. It is capped at ₹2,500 a year by the Constitution and has nothing to do with income tax. Your employer deducts it monthly and pays it to the state.
**Q: Is professional tax the same as income tax?** No. Professional tax is a state tax capped at ₹2,500 a year, deducted from salary regardless of your income tax. Income tax is a central tax on your total annual income at slab rates. They are separate — you can owe both, and PT is itself deductible from your taxable income.
**Q: How is professional tax calculated?** Professional tax is based on your gross monthly salary and your state's slab. Each state sets income bands with a fixed PT amount — for example, in Maharashtra anyone earning over ₹10,000 a month pays ₹2,500 a year (₹200 monthly, ₹300 in one month). The yearly total can never exceed ₹2,500.
**Last updated:** 2026-06-10

### NPS Calculator
**URL:** https://calcrux.com/tools/india-business/nps-calculator
**What it does:** Free NPS calculator for India — project your National Pension System corpus, tax-free lump sum and monthly pension at 60, with the new 80% rule. FY 2025-26.
**Key outputs:** Total Corpus at Retirement, Monthly Pension, Lump Sum at 60, Total Invested, Annuity Corpus, Taxable Lump Sum, Pension in Today's Money
**Core formula:** Corpus at retirement: Corpus = P × [((1 + i)^n − 1) / i] × (1 + i)
**Region:** IN only (INR)
**Q: What is an NPS calculator?** An NPS calculator projects your National Pension System corpus at retirement and the pension it buys. You enter your age, monthly contribution and expected return; it shows the corpus at 60, the lump sum you can withdraw, and your monthly pension from the annuity.
**Q: How is the NPS pension calculated?** Your contributions grow like a SIP until you exit at 60, building a corpus. At 60 you take part of it as a lump sum and use the rest to buy an annuity. The monthly pension is the annuity corpus × the annuity rate ÷ 12 — for example, ₹45 lakh at 6% pays about ₹22,500 a month.
**Q: How much of the NPS corpus is tax-free?** Up to 60% of the corpus taken as a lump sum at 60 is tax-free under Section 10(12A). The 2025 rules let non-government subscribers withdraw up to 80%, but the slice above 60% is taxable at your income-tax slab. The pension from the annuity is always taxable.
**Last updated:** 2026-06-11

### PPF Calculator
**URL:** https://calcrux.com/tools/india-business/ppf-calculator
**What it does:** Free PPF calculator for India — project your Public Provident Fund maturity and tax-free interest at the 7.1% rate, for yearly or monthly deposits. FY 2025-26.
**Key outputs:** Maturity Value, Total Invested, Total Interest, Maturity if Extended +5 Years
**Core formula:** Yearly deposit (annuity-due): M = P × [((1 + i)^n − 1) / i] × (1 + i)
**Region:** IN only (INR)
**Q: What is a PPF calculator?** A PPF calculator projects what your Public Provident Fund grows to at maturity. You enter your yearly deposit, the interest rate and tenure; it shows the maturity value, the total you invested, and the tax-free interest you earn over 15 years or more.
**Q: How is PPF interest calculated?** PPF interest is compounded yearly but accrues on the lowest balance between the 5th and the last day of each month. A deposit made by 5 April earns a full year of interest; depositing monthly earns slightly less. For FY 2025-26 the rate is 7.1%.
**Q: What is the PPF interest rate for 2025-26?** The PPF interest rate is 7.1% per annum for FY 2025-26, held at that level through the January–March 2026 quarter. The government reviews it every quarter, so it can change — this calculator lets you set any rate to model your own assumption.
**Last updated:** 2026-06-11

### PPF Goal Calculator
**URL:** https://calcrux.com/tools/india-business/ppf-goal-calculator
**What it does:** Free PPF goal calculator — work backwards from a target like ₹1 crore to the yearly or monthly deposit you need, with the ₹1.5 lakh cap built in. FY 2025-26.
**Key outputs:** Required Yearly Investment, Required Monthly Investment, Total You'll Invest, Max PPF Can Give, Shortfall vs Goal, Head Start from Current Balance, Future Cost of Goal
**Core formula:** Required yearly deposit: Required = Target ÷ [(1 + r × t) × ((1 + r)^n − 1) ÷ r]
**Region:** IN only (INR)
**Q: What is a PPF goal calculator?** A PPF goal calculator works backwards from a target maturity amount to the yearly deposit you need. You enter the corpus you want, the tenure and the rate; it returns the required yearly and monthly investment — and flags if it exceeds the ₹1.5 lakh PPF limit.
**Q: How much should I invest in PPF to get ₹1 crore?** About ₹1.45 lakh a year at 7.1% reaches ₹1 crore in 25 years. In 15 years it is impossible in PPF alone — you would need ₹3.7 lakh a year, well above the ₹1.5 lakh limit, so you must extend the tenure or add another investment.
**Q: How is the required PPF investment calculated?** Required yearly deposit = target ÷ [(1 + rate × timing) × ((1+rate)^years − 1) ÷ rate]. It inverts the PPF maturity formula, where the timing factor is 1 for a yearly lump and about 0.54 for monthly deposits. The monthly figure is the yearly amount ÷ 12.
**Last updated:** 2026-06-12

### Sukanya Samriddhi Yojana Calculator
**URL:** https://calcrux.com/tools/india-business/sukanya-samriddhi-yojana-calculator
**What it does:** Free Sukanya Samriddhi Yojana (SSY) calculator — the tax-free maturity at 21 at 8.2%, the 50% education withdrawal at 18, and the inflation-adjusted real value.
**Key outputs:** Maturity Amount (at 21 yrs), Total Deposited, Total Interest, Balance When Deposits Stop, Education Withdrawal at 18, Maturity in Today's Money, Her Age at Maturity
**Core formula:** Deposit phase (years 1–15): Each year: Balance = Balance × (1 + r) + Deposit × (1 + r × t)
**Region:** IN only (INR)
**Q: What is a Sukanya Samriddhi Yojana calculator?** An SSY calculator projects what a Sukanya Samriddhi Yojana account grows to at maturity. You enter the yearly deposit, the interest rate and the girl's age; it shows the tax-free maturity amount at 21 years, the total you deposit, and the interest earned.
**Q: What is the SSY interest rate for 2025-26?** The SSY interest rate is 8.2% per annum for FY 2025-26 — among the highest of all small-savings schemes. The government reviews it every quarter, so it can change; this calculator lets you set any rate to model your own assumption.
**Q: How is the SSY maturity amount calculated?** You deposit for the first 15 years; the account then keeps compounding for 6 more years and matures at 21. Interest is compounded yearly at 8.2%. So a year-1 deposit grows for 21 years, while the balance at year 15 earns interest right up to maturity.
**Last updated:** 2026-06-14

### FD Calculator
**URL:** https://calcrux.com/tools/india-business/fd-calculator
**What it does:** Free FD calculator for India — fixed deposit maturity, interest and TDS with quarterly compounding, plus the real post-tax return after your slab and inflation.
**Key outputs:** Maturity Value, Total Interest, You Receive (after TDS), TDS on Interest, Effective Annual Yield, Maturity After Your Tax, Real Value (Today's Money)
**Core formula:** Compound maturity: Maturity = P × (1 + r/n)^(n × t)
**Region:** IN only (INR)
**Q: What is an FD calculator?** An FD calculator works out what a fixed deposit grows to at maturity. You enter the deposit amount, interest rate and tenure; it returns the maturity value, the interest earned, and the TDS the bank deducts on that interest.
**Q: How is FD maturity calculated?** Maturity = P × (1 + r/n)^(n × t), where P is the deposit, r the annual rate, n the compounding frequency (4 for quarterly), and t the years. Indian banks compound quarterly, so ₹5 lakh at 7% for 5 years grows to about ₹7.07 lakh.
**Q: What is the maturity of ₹5 lakh FD at 7%?** ₹5 lakh at 7% for 5 years, compounded quarterly, matures at about ₹7,07,389 — roughly ₹2,07,389 of interest. The effective annual yield is about 7.19% because the interest compounds four times a year.
**Last updated:** 2026-06-14

### RD Calculator
**URL:** https://calcrux.com/tools/india-business/rd-calculator
**What it does:** Free RD calculator for India — recurring deposit maturity, interest and TDS from monthly deposits, plus the real post-tax maturity after your slab and inflation.
**Key outputs:** Maturity Value, Total Interest, You Receive (after TDS), Total Deposited, TDS on Interest, Maturity After Your Tax, Real Value (Today's Money)
**Core formula:** RD maturity: M = R × [(1 + i)^n − 1] / (1 − (1 + i)^(−1/3))
**Region:** IN only (INR)
**Q: What is an RD calculator?** An RD calculator works out what a recurring deposit grows to at maturity. You enter the monthly deposit, interest rate and tenure; it returns the maturity value, the interest earned, the total deposited, and the TDS the bank deducts.
**Q: How is RD maturity calculated?** Maturity = R × [(1+i)^n − 1] / (1 − (1+i)^(−1/3)), where R is the monthly deposit, i is the quarterly rate (annual rate ÷ 400) and n is the number of quarters. Each deposit earns interest from its date, compounded quarterly.
**Q: What is the maturity of ₹5,000 a month RD at 7%?** ₹5,000 a month at 7% for 5 years matures at about ₹3,59,664 — you deposit ₹3,00,000 over 60 months and earn roughly ₹59,664 of interest, compounded quarterly.
**Last updated:** 2026-06-14

### NSC Calculator
**URL:** https://calcrux.com/tools/india-business/nsc-calculator
**What it does:** Free NSC calculator — National Savings Certificate maturity and interest at 7.7% over 5 years, the 80C reinvested-interest benefit, and the net after tax.
**Key outputs:** Maturity Value (5 yrs), Total Interest, Reinvested Interest (80C), Final-Year Interest (taxable), Eligible for 80C, Maturity After Your Tax, Real Value (Today's Money)
**Core formula:** Maturity value: Maturity = P × (1 + r)^5
**Region:** IN only (INR)
**Q: What is an NSC calculator?** An NSC calculator works out what a National Savings Certificate grows to after its 5-year term. You enter the investment and the rate; it returns the maturity value, the interest earned, and how the interest splits for tax purposes.
**Q: How is NSC maturity calculated?** Maturity = P × (1 + r)^5, where P is the investment and r is the annual rate. Interest is compounded yearly and paid in full at the end of 5 years. At 7.7%, ₹1,000 grows to about ₹1,449.
**Q: What is the maturity of ₹1 lakh NSC at 7.7%?** ₹1 lakh in NSC at 7.7% grows to about ₹1,44,903 after 5 years — roughly ₹44,903 of interest, compounded annually and paid at maturity along with the principal.
**Last updated:** 2026-06-14

### SCSS Calculator
**URL:** https://calcrux.com/tools/india-business/scss-calculator
**What it does:** Free SCSS calculator — the quarterly income from the Senior Citizen Savings Scheme at 8.2%, plus the net income after the ₹50k 80TTB exemption and your slab.
**Key outputs:** Quarterly Income, Annual Income, Total Interest (5 yrs), TDS per Year, Eligible for 80C, Net Quarterly Income, Real Income Yield
**Core formula:** Quarterly income: Quarterly = Investment × rate ÷ 4
**Region:** IN only (INR)
**Q: What is an SCSS calculator?** An SCSS calculator works out the income from the Senior Citizen Savings Scheme. You enter the investment and rate; it returns the quarterly income, the annual income, and the total interest over the 5-year term, plus the TDS and 80C position.
**Q: How is SCSS interest calculated?** SCSS pays simple interest quarterly — it does not compound. Quarterly income = investment × rate ÷ 4. At 8.2%, ₹15 lakh pays ₹30,750 a quarter (₹1,23,000 a year), and the ₹15 lakh principal is returned at maturity.
**Q: What is the quarterly income on ₹15 lakh SCSS?** ₹15 lakh at 8.2% pays ₹30,750 every quarter — that is ₹1,23,000 a year, or ₹6,15,000 of interest over the 5-year term. The ₹15 lakh principal comes back to you at maturity.
**Last updated:** 2026-06-14

### Post Office MIS Calculator
**URL:** https://calcrux.com/tools/india-business/post-office-mis-calculator
**What it does:** Free Post Office MIS calculator — the monthly income from the Post Office Monthly Income Scheme at 7.4%, plus the net income after tax and the real yield after inflation.
**Key outputs:** Monthly Income, Annual Income, Total Interest (5 yrs), Principal Returned, Total You Receive, Net Monthly Income, Real Income Yield
**Core formula:** Monthly income: Monthly = Investment × rate ÷ 12
**Region:** IN only (INR)
**Q: What is a Post Office MIS calculator?** A Post Office MIS calculator works out the income from the Post Office Monthly Income Scheme. You enter the investment, account type and rate; it returns the monthly income, the annual income, and the total interest over the 5-year term, plus the principal you get back.
**Q: How is Post Office MIS interest calculated?** POMIS pays simple interest monthly — it does not compound. Monthly income = investment × rate ÷ 12. At 7.4%, ₹9 lakh pays ₹5,550 a month (₹66,600 a year), and the ₹9 lakh principal is returned at maturity.
**Q: What is the monthly income on ₹9 lakh in Post Office MIS?** ₹9 lakh — the single-account maximum — pays ₹5,550 every month at 7.4%. That is ₹66,600 a year, or ₹3,33,000 of interest over the 5-year term, with the ₹9 lakh principal returned at the end.
**Last updated:** 2026-06-14

### KVP Calculator
**URL:** https://calcrux.com/tools/india-business/kvp-calculator
**What it does:** Free KVP calculator — how long Kisan Vikas Patra takes to double your money at 7.5% (115 months), the maturity, and the real return after tax and inflation.
**Key outputs:** Maturity Value, Time to Double, Interest Earned, Doubling Period, Total Return, Maturity After Your Tax, Real Value (Today's Money)
**Core formula:** Doubling period: Months = 12 × ln(2) ÷ ln(1 + rate)
**Region:** IN only (INR)
**Q: What is a KVP calculator?** A KVP calculator shows how long Kisan Vikas Patra takes to double your money and the maturity value. You enter the investment and rate; it returns the doubling period, the maturity value (twice your investment), and the interest earned.
**Q: How long does KVP take to double money?** At the current 7.5% rate (FY 2025-26), KVP doubles your money in 115 months — that is 9 years and 7 months. The doubling period is set by the government and changes only when the interest rate changes.
**Q: How is the KVP doubling period calculated?** The doubling period is the time for money to double at the given rate, compounded annually: months = 12 × ln(2) ÷ ln(1 + rate). At 7.5% that works out to 115 months, and the maturity is set to exactly twice the investment.
**Last updated:** 2026-06-14

### APY Calculator
**URL:** https://calcrux.com/tools/india-business/apy-calculator
**What it does:** Free APY calculator — the exact Atal Pension Yojana monthly contribution for your age and ₹1,000–₹5,000 pension, the nominee corpus, and the pension's real value.
**Key outputs:** Monthly Contribution, Monthly Pension at 60, Total You Contribute, Years to Contribute, Corpus to Nominee, Pension in Today's Money
**Core formula:** Official chart, not a formula: Contribution = chart[entry age][pension level]
**Region:** IN only (INR)
**Q: What is an APY calculator?** An APY calculator shows the exact monthly contribution for the Atal Pension Yojana based on your current age and the pension you want. It also shows the total you pay in, the years to contribute, and the corpus returned to your nominee.
**Q: How is the APY contribution calculated?** It is not a formula — APY uses a fixed government chart. The monthly contribution is read from the PFRDA table by your entry age (18–40) and chosen pension (₹1,000–₹5,000). For example, joining at 25 for a ₹5,000 pension costs ₹376 a month.
**Q: How much should I pay for a ₹5,000 pension in APY?** It depends on your age. At 18 you pay just ₹210 a month, at 25 it is ₹376, at 30 it is ₹577, and at 40 it is ₹1,454 — for the same ₹5,000 monthly pension. The earlier you join, the less you pay.
**Last updated:** 2026-06-14

### Capital Gains Tax Calculator
**URL:** https://calcrux.com/tools/india-business/capital-gains-tax-calculator
**What it does:** Free capital gains tax calculator for FY 2025-26 — STCG/LTCG on equity, property, gold and debt funds at the new 2024 rates, with the ₹1.25L exemption and indexation.
**Key outputs:** Capital Gain, Tax Payable, Gain After Tax, Gain Type, Taxable Gain, Effective Tax Rate
**Core formula:** The gain: Gain = Sale price − Purchase price − Costs
**Region:** IN only (INR)
**Q: What is a capital gains tax calculator?** A capital gains tax calculator works out the tax on profit from selling an asset. You enter the asset type, purchase and sale prices, and holding period; it returns the gain, whether it is short- or long-term, the tax payable, and what you keep after tax.
**Q: How is capital gains tax calculated in India for 2025-26?** First the gain = sale price − purchase price − transfer costs. Then the rate depends on the asset and holding period: listed equity is 20% short-term or 12.5% long-term (above ₹1.25 lakh); property, gold and unlisted shares are slab-rate short-term or 12.5% long-term; plus 4% cess on the tax.
**Q: What is the LTCG tax rate on shares now?** Long-term capital gains on listed shares and equity mutual funds are taxed at 12.5% (up from 10%), on gains above ₹1.25 lakh in a year (up from ₹1 lakh). The asset must be held over 12 months. These rates apply to sales on or after 23 July 2024.
**Last updated:** 2026-06-14

### 80C Calculator
**URL:** https://calcrux.com/tools/india-business/section-80c-calculator
**What it does:** Free 80C calculator — total your EPF, PPF, ELSS and insurance, track the ₹1.5 lakh limit, add NPS 80CCD(1B) and employer NPS 80CCD(2), and see the tax you save.
**Key outputs:** Total 80C Investment, Total Deduction, Tax Saved, 80C Deduction (capped), 80C Room Left, NPS Extra (80CCD-1B), Employer NPS (80CCD-2)
**Core formula:** Eligible deduction: Eligible 80C = min(total invested, ₹1.5L)
**Region:** IN only (INR)
**Q: What is an 80C calculator?** An 80C calculator adds up your tax-saving investments — EPF, PPF, ELSS, insurance and more — caps them at the ₹1.5 lakh limit, and shows the tax you save at your slab. It also tracks the extra ₹50,000 NPS deduction under 80CCD(1B).
**Q: What is the 80C deduction limit?** Section 80C allows a deduction of up to ₹1.5 lakh a year. Investing more than that earns no extra 80C deduction — though NPS adds a separate ₹50,000 under 80CCD(1B), taking the combined limit to ₹2 lakh.
**Q: How much tax does 80C save?** The saving is your deduction times your slab rate, plus 4% cess. At 30%, a full ₹1.5 lakh 80C deduction saves ₹46,800; adding ₹50,000 of NPS takes the total to ₹62,400. At 20% the ₹1.5 lakh saves ₹31,200.
**Last updated:** 2026-06-14

### Home Loan Tax Benefit Calculator
**URL:** https://calcrux.com/tools/india-business/home-loan-tax-benefit-calculator
**What it does:** Free home loan tax benefit calculator — see your Section 24(b) interest and 80C principal deductions, 80EE/80EEA extra, and the income tax you save. FY 2025-26.
**Key outputs:** Interest Deduction (Sec 24b), Principal Deduction (80C), Tax Saved This Year, Total Deduction, Extra Interest (80EE/80EEA), Monthly EMI, Interest This Year, Total Interest (Lifetime)
**Core formula:** Interest deduction (Section 24b): Interest deduction = min(year's interest, ₹2,00,000)
**Region:** IN only (INR)
**Q: What is a home loan tax benefit calculator?** It shows the income tax you save on a home loan — the interest deduction under Section 24(b) (up to ₹2 lakh), the principal deduction under Section 80C (up to ₹1.5 lakh), and any 80EE/80EEA extra. Enter your loan and slab to see the saving.
**Q: How much tax benefit can I get on a home loan?** Under the old regime, up to ₹2 lakh of interest (Section 24b) plus up to ₹1.5 lakh of principal (Section 80C) a year, for a self-occupied home. First-time buyers may add ₹50,000 (80EE) or ₹1.5 lakh (80EEA) of interest if their loan qualifies.
**Q: What is the Section 24(b) home loan interest limit?** For a self-occupied house, interest is deductible up to ₹2,00,000 a year under Section 24(b). For a let-out house there is no cap on the interest itself, but the loss you set off against other income is limited to ₹2,00,000 a year.
**Last updated:** 2026-06-14

### 80D Calculator
**URL:** https://calcrux.com/tools/india-business/section-80d-calculator
**What it does:** Free 80D calculator — your health-insurance tax deduction for self, family and parents, with the ₹50,000 senior limits and preventive check-up. FY 2025-26.
**Key outputs:** Self & Family Deduction, Parents Deduction, Tax Saved, Total 80D Deduction, Maximum Possible, Room Left, Preventive Counted
**Core formula:** Self & family bucket: Self = min(premium + min(preventive, ₹5,000), limit)
**Region:** IN only (INR)
**Q: What is an 80D calculator?** An 80D calculator works out your health-insurance tax deduction. It adds your premiums for self/family and parents, applies the ₹25,000 (or ₹50,000 senior) limits and the ₹5,000 preventive cap, and shows the tax you save at your slab.
**Q: What is the 80D deduction limit?** Up to ₹25,000 for self, spouse and children, plus a separate ₹25,000 for parents. Each limit rises to ₹50,000 when that group is a senior citizen (60+), so the combined maximum is ₹1,00,000 when both you and your parents are seniors.
**Q: How much tax does 80D save?** The saving is your deduction times your slab rate, plus 4% cess. At the 30% slab, a ₹25,000 deduction saves ₹7,800, ₹50,000 saves ₹15,600, and the full ₹1,00,000 saves ₹31,200. At 20% the ₹50,000 saves ₹10,400.
**Last updated:** 2026-06-14

### 80E Calculator
**URL:** https://calcrux.com/tools/india-business/section-80e-calculator
**What it does:** Free 80E calculator — find your education-loan interest deduction (no upper limit) and the tax you save over the 8-year window, at your slab. FY 2025-26.
**Key outputs:** Interest Deduction This Year, Tax Saved This Year, Total Tax Saved (8 yrs), Monthly EMI, Interest in 8-yr Window, Total Interest (Lifetime), Interest Beyond Year 8
**Core formula:** Yearly deduction: Deduction = interest paid that year (no cap)
**Region:** IN only (INR)
**Q: What is an 80E calculator?** An 80E calculator works out the tax you save on an education loan. It finds the interest you pay each year, treats all of it as deductible under Section 80E (there is no upper limit), and shows the tax saved at your slab over the 8-year window.
**Q: What is the 80E deduction limit?** There is no upper limit on the amount. Section 80E lets you deduct the entire interest paid on an education loan, however large — unlike 80C or 80D, which cap the deduction. Only the interest qualifies, not the principal.
**Q: For how many years can I claim 80E?** For a maximum of 8 years — the year you start repaying plus the next seven — or until the interest is fully paid, whichever is earlier. Interest paid in year 9 onward earns no 80E deduction.
**Last updated:** 2026-06-14

### 80G Calculator
**URL:** https://calcrux.com/tools/india-business/section-80g-calculator
**What it does:** Free 80G calculator — your tax deduction on donations to charities and funds, with the 100% / 50% rates and the 10% qualifying limit, plus the tax you save.
**Key outputs:** 80G Deduction, Tax Saved, Eligible Donation, Qualifying Limit (10%)
**Core formula:** Qualifying limit: Limit = 10% × adjusted gross total income
**Region:** IN only (INR)
**Q: What is an 80G calculator?** An 80G calculator works out your tax deduction on charitable donations. It applies the institution's 100% or 50% rate, caps limit-category donations at 10% of your adjusted income, and shows the tax you save at your slab.
**Q: How much tax do I save on a donation under 80G?** It depends on the rate and your slab. A ₹50,000 donation at 50% gives a ₹25,000 deduction, saving ₹7,800 at the 30% slab. The same donation at 100% gives a ₹50,000 deduction, saving ₹15,600.
**Q: What is the 80G deduction limit?** There is no overall cap, but two categories are limited: donations "subject to the qualifying limit" count only up to 10% of your adjusted gross total income. Donations to "no limit" funds have no such ceiling.
**Last updated:** 2026-06-14

### 80TTA & 80TTB Calculator
**URL:** https://calcrux.com/tools/india-business/section-80tta-80ttb-calculator
**What it does:** Free 80TTA & 80TTB calculator — your tax-free deduction on savings and deposit interest (₹10,000 under 60, ₹50,000 for seniors), and the tax it saves.
**Key outputs:** Interest Deduction, Tax Saved, Taxable Interest, Eligible Interest, Deduction Limit
**Core formula:** Eligible interest: 80TTA: savings only · 80TTB: savings + all deposits
**Region:** IN only (INR)
**Q: What is an 80TTA / 80TTB calculator?** It works out the tax-free deduction on your interest income. Under 60 you get 80TTA — up to ₹10,000 on savings-account interest. At 60 or above you get 80TTB — up to ₹50,000 on all deposit interest, including FDs.
**Q: What is the difference between 80TTA and 80TTB?** 80TTA (under 60) covers only savings-account interest, up to ₹10,000. 80TTB (60+) covers all deposit interest — savings, FD, RD and post office — up to ₹50,000. A senior claims 80TTB instead of 80TTA, not both.
**Q: Is FD interest tax-free under 80TTA?** No. For those under 60, Section 80TTA covers only savings-account interest — FD and RD interest is fully taxable. FD interest becomes deductible (up to ₹50,000) only for senior citizens under 80TTB.
**Last updated:** 2026-06-14

### Salary Breakup Calculator
**URL:** https://calcrux.com/tools/india-business/salary-breakup-calculator
**What it does:** Free salary breakup calculator — split your CTC into Basic, HRA, PF, gratuity and special allowance, and see the monthly take-home before tax. India FY 2025-26.
**Key outputs:** Monthly Take-Home (pre-tax), Annual Basic, Annual Gross Salary, Annual HRA, Special Allowance, Employer PF, Employee PF, Gratuity (accrued), Professional Tax
**Core formula:** Core components: Basic = basic% × CTC ; HRA = 50%/40% × Basic
**Region:** IN only (INR)
**Q: What is a salary breakup calculator?** It splits your annual CTC into its components — Basic, HRA, employer and employee PF, gratuity and special allowance — and shows the monthly take-home before income tax. It is the structure behind your offer letter and payslip.
**Q: How is salary broken up from CTC?** Basic is set as a percentage of CTC (usually 40–50%). HRA is 50% of Basic in metros (40% elsewhere), PF is 12% of Basic, and gratuity is 4.81% of Basic. Special allowance is whatever is left of the CTC after these.
**Q: What is the difference between CTC, gross and take-home?** CTC is the employer's total cost, including employer PF and gratuity. Gross salary is CTC minus those, paid to you. Take-home is gross minus employee PF, professional tax and income tax — what reaches your bank.
**Last updated:** 2026-06-15

### EMI Calculator
**URL:** https://calcrux.com/tools/india-business/emi-calculator
**What it does:** Free EMI calculator — your monthly EMI, total interest and total payment for any home, car or personal loan, with a year-by-year breakdown. Reducing balance.
**Key outputs:** Monthly EMI, Total Interest, Total Payment, Interest as % of Loan, Total Instalments
**Core formula:** EMI: EMI = P · R · (1+R)^N / ((1+R)^N − 1)
**Region:** IN only (INR)
**Q: What is an EMI calculator?** An EMI calculator works out the fixed monthly instalment on a loan from the amount, interest rate and tenure. It also shows the total interest, the total you repay, and how each EMI splits between interest and principal over time.
**Q: How is EMI calculated?** EMI = P × R × (1+R)^N ÷ [(1+R)^N − 1], where P is the loan amount, R is the monthly rate (annual ÷ 12 ÷ 100) and N is the number of months. The result is a level monthly payment for the whole tenure.
**Q: What is the EMI on a ₹25 lakh loan at 9% for 20 years?** About ₹22,493 a month. Over the 20 years you repay roughly ₹53.98 lakh in all — of which about ₹28.98 lakh is interest, more than the amount you borrowed.
**Last updated:** 2026-06-14

### Loan Prepayment Calculator
**URL:** https://calcrux.com/tools/india-business/loan-prepayment-calculator
**What it does:** Free loan prepayment calculator — the interest saved and how much sooner you finish, comparing reduce-tenure vs reduce-EMI on a home, car or personal loan.
**Key outputs:** Interest Saved, New Tenure (Years), New EMI, Months Saved, Interest With Prepayment, Interest Without Prepayment, Current EMI
**Core formula:** Reduce tenure: Keep EMI fixed; apply extra to principal → payoff sooner
**Region:** IN only (INR)
**Q: What is a loan prepayment calculator?** It shows how much interest you save by prepaying a loan — a one-time lump sum and/or extra each month. It compares the two outcomes lenders offer: reducing the tenure (finish sooner) or reducing the EMI (lower monthly payment).
**Q: Should I reduce the tenure or the EMI after prepaying?** Reducing the tenure saves more interest, because you keep paying the same EMI while the principal falls faster. Reducing the EMI eases monthly cash flow but saves less. If the EMI is comfortable, choose tenure reduction.
**Q: How much interest does prepayment save?** It depends on the amount and timing. For example, prepaying ₹5 lakh after one year on a ₹30 lakh, 9%, 20-year loan saves about ₹15.5 lakh and ends the loan 6 years early — if you reduce the tenure rather than the EMI.
**Last updated:** 2026-06-14

### Loan Eligibility Calculator
**URL:** https://calcrux.com/tools/india-business/loan-eligibility-calculator
**What it does:** Free loan eligibility calculator — how much loan you can get from your income using the FOIR method, after existing EMIs, at your chosen rate and tenure.
**Key outputs:** Eligible Loan Amount, Affordable EMI, Current FOIR, Total EMI Capacity, Income Left After EMIs, Total Interest, Total Repayment
**Core formula:** EMI capacity: Allowed EMI = net income × FOIR%
**Region:** IN only (INR)
**Q: What is a loan eligibility calculator?** It estimates how much loan you can get based on your income. Using the FOIR method, it finds the largest EMI you can carry after existing obligations, then works back to the loan amount at your chosen rate and tenure.
**Q: What is FOIR?** FOIR is the Fixed Obligation to Income Ratio — your total monthly EMIs and fixed obligations as a percentage of net income. Lenders cap it (usually 40–55%) to make sure your repayments stay affordable.
**Q: How is loan eligibility calculated?** Multiply your net income by the FOIR to get the most your EMIs can total, subtract existing obligations to get the EMI you can still take on, then convert that EMI into a loan amount at the chosen rate and tenure.
**Last updated:** 2026-06-14

### Loan Balance Transfer Calculator
**URL:** https://calcrux.com/tools/india-business/loan-balance-transfer-calculator
**What it does:** Free loan balance transfer calculator — the interest you save by switching to a lower rate, net of processing fees, plus your new EMI and the break-even period.
**Key outputs:** Net Savings, EMI Drop, Break-even (Months), Gross Interest Saved, Transfer Cost, Current EMI, New EMI
**Core formula:** Gross interest saved: Saved = (current EMI − new EMI) × remaining months
**Region:** IN only (INR)
**Q: What is a loan balance transfer calculator?** It shows what you save by moving your outstanding loan to a lender with a lower rate. It works out the EMI drop, the interest saved over the remaining tenure, the cost of switching, the net saving, and how soon the switch pays for itself.
**Q: What is a home loan balance transfer?** It is moving your existing loan to a new lender that offers a lower interest rate. The new lender clears your old loan, and you repay them instead — usually at a lower EMI over the same remaining tenure.
**Q: How much can I save with a balance transfer?** It depends on the rate gap, balance and tenure left. For example, ₹40 lakh outstanding with 10 years left, switching from 9.5% to 8.5%, drops the EMI by about ₹2,165 and saves around ₹2.26 lakh net of typical fees.
**Last updated:** 2026-06-14

### TDS on Salary Calculator
**URL:** https://calcrux.com/tools/india-business/tds-on-salary-calculator
**What it does:** Free TDS on salary calculator — the monthly TDS under Section 192 for the old and new regimes, with mid-year joining and TDS-already-deducted handling. FY 2025-26.
**Key outputs:** Monthly TDS, Monthly In-Hand, Annual Tax (TDS), Taxable Income, Effective Tax Rate, Tax Still to Deduct, Annual In-Hand
**Core formula:** Annual tax: Tax on (salary − deductions), with rebate & cess
**Region:** IN only (INR)
**Q: What is a TDS on salary calculator?** A TDS on salary calculator shows how much tax your employer deducts each month from your pay under Section 192. It works out the annual tax on your salary, then divides it across the months left in the year to give the monthly TDS.
**Q: How is TDS on salary calculated?** The employer estimates your annual income tax on the salary (after the standard deduction and any declared deductions), then deducts it in equal monthly instalments. Monthly TDS = annual tax ÷ months remaining in the financial year.
**Q: How much TDS is deducted on a ₹15 lakh salary?** Under the new regime, ₹15 lakh has a taxable income of ₹14.25 lakh, an annual tax of about ₹97,500, and a monthly TDS of around ₹8,125 over a full year. The old regime depends on your deductions.
**Last updated:** 2026-06-14

### Salary Hike Calculator
**URL:** https://calcrux.com/tools/india-business/salary-hike-calculator
**What it does:** Free salary hike calculator — find your hike percentage or new salary, the monthly and annual increase, and your real raise after inflation. Updated 2026.
**Key outputs:** Hike Percentage, New Salary, Salary Increase, Monthly Increase, Annual Increase, Real Increase (after inflation)
**Core formula:** Hike percentage: Hike % = (new − old) ÷ old × 100
**Region:** IN only (INR)
**Q: What is a salary hike calculator?** A salary hike calculator works out either your hike percentage from your old and new salary, or your new salary from a hike percentage. It also shows the increase per month and per year, so you can see exactly what a raise is worth.
**Q: How do I calculate salary hike percentage?** Hike % = (new salary − old salary) ÷ old salary × 100. For example, going from ₹50,000 to ₹60,000 is (10,000 ÷ 50,000) × 100 = 20%. Enter both figures and the calculator does it instantly.
**Q: How do I find my new salary after a hike?** New salary = current salary × (1 + hike% ÷ 100). A 10% hike on ₹50,000 gives ₹50,000 × 1.10 = ₹55,000. Choose "the hike %" mode, enter the percentage, and the calculator returns the new figure.
**Last updated:** 2026-06-14

### Leave Encashment Calculator
**URL:** https://calcrux.com/tools/india-business/leave-encashment-calculator
**What it does:** Free leave encashment calculator — find the Section 10(10AA) exempt amount (least of four limits, ₹25 lakh lifetime), the tax on the taxable part, and net in hand.
**Key outputs:** Leave Encashment, Tax-Exempt Amount, Taxable Amount, Tax on Taxable Part, Net in Hand, Per-Day Salary, Exemption Limit, Exemption Capped By
**Core formula:** Leave encashment: Encashment = leave days × (Basic+DA ÷ 30)
**Region:** IN only (INR)
**Q: What is a leave encashment calculator?** A leave encashment calculator values the payment for your unused earned leave and works out how much is tax-free. You enter your Basic + DA, the leave days and years of service; it returns the encashment, the exempt amount under Section 10(10AA), and the taxable part.
**Q: How is leave encashment calculated?** Leave encashment = leave days encashed × per-day salary, where per-day salary = monthly (Basic + DA) ÷ 30. For example, 350 days at ₹60,000 Basic + DA is 350 × ₹2,000 = ₹7,00,000.
**Q: Is leave encashment taxable?** On retirement, government employees are fully exempt. Non-government employees get an exemption up to the least of four limits, and only the excess is taxable. Leave encashed while still in service is fully taxable.
**Last updated:** 2026-06-14

### Statutory Bonus Calculator
**URL:** https://calcrux.com/tools/india-business/statutory-bonus-calculator
**What it does:** Free statutory bonus calculator — your bonus under the Payment of Bonus Act (now the Code on Wages), the 8.33% minimum to 20% maximum, ₹7,000 ceiling, and net after tax.
**Key outputs:** Bonus Payable, Minimum (8.33%), Maximum (20%), Net in Hand, Tax on Bonus, Wage Used, Eligibility
**Core formula:** Bonus wage: Wage = min(Basic+DA, max(₹7,000, state min wage))
**Region:** IN only (INR)
**Q: What is a statutory bonus calculator?** A statutory bonus calculator works out the bonus payable under the Payment of Bonus Act, 1965. You enter your monthly Basic + DA, the bonus rate and months worked; it returns the bonus, the 8.33% minimum and 20% maximum, and the capped wage used.
**Q: How is statutory bonus calculated?** Bonus = bonus wage × 12 × bonus%, where the bonus wage is capped at ₹7,000 a month (or the state minimum wage if higher). At 8.33%, the bonus on the ₹7,000 ceiling is ₹6,997 a year; at 20% it is ₹16,800.
**Q: Who is eligible for statutory bonus?** Employees earning monthly wages (Basic + DA) up to ₹21,000 and who have worked at least 30 days in the year are covered. Above ₹21,000, any bonus is at the employer's discretion, not a statutory right.
**Last updated:** 2026-06-14

### GST Late Fee & Interest Calculator
**URL:** https://calcrux.com/tools/india-business/gst-late-fee-calculator
**What it does:** Free GST late fee & interest calculator for GSTR-3B and GSTR-1 — the per-day fee (capped by turnover) and 18% interest, plus what each extra day costs. FY 2025-26.
**Key outputs:** Late Fee, Interest, Total Late Charges, Late Fee Per Day, Late Fee Cap, Total Payable (incl. tax), CGST Late Fee, SGST Late Fee, Interest Per Day
**Core formula:** Late fee: Fee = min(per-day × days, cap)
**Region:** IN only (INR)
**Q: What is a GST late fee and interest calculator?** It works out the cost of filing a GST return late — the per-day late fee under Section 47 (capped by turnover) and the 18% interest under Section 50 on the tax paid late. Enter the days late, tax and turnover to see the total.
**Q: How much is the GST late fee per day?** For a normal GSTR-3B it is ₹50 a day (₹25 CGST + ₹25 SGST). For a NIL return it is ₹20 a day (₹10 + ₹10). The fee is capped depending on your return type and turnover.
**Q: What is the maximum GST late fee?** A NIL return is capped at ₹500. For a normal return, the cap is ₹2,000 for turnover up to ₹1.5 crore, ₹5,000 for ₹1.5–5 crore, and ₹10,000 above ₹5 crore (each split equally between CGST and SGST).
**Last updated:** 2026-06-14

---

## Ecosystem 3 — Manufacturing & ERP Operations

Production planning, costing, and maintenance tools for manufacturers

### OEE Calculator
**URL:** https://calcrux.com/tools/manufacturing/oee-calculator
**What it does:** Free OEE calculator: Availability, Performance, and Quality per ISO 22400, with Six Big Losses breakdown to find your top improvement lever. Calculate free →
**Key outputs:** OEE Score, Availability, Performance, Quality Rate, Run Time, Good Pieces, Speed Loss, Quality Loss
**Core formula:** Availability: Availability = Run Time ÷ Planned Production Time
**Q: What is OEE?** OEE (Overall Equipment Effectiveness) measures how much of your planned production time is truly productive. It multiplies Availability, Performance, and Quality to give a single percentage score for machine efficiency.
**Q: What is the OEE formula?** OEE = Availability × Performance × Quality. Each factor is a ratio from 0 to 1, so a result of 0.85 means 85% of planned production time generated good output at full speed.
**Q: What does 85% world-class OEE mean?** 85% is the widely cited world-class benchmark, originally from Seiichi Nakajima's Total Productive Maintenance work. It means 15% of planned production time is lost across all three factors. Few plants sustain it.
**Last updated:** 2026-06-07

### MTBF & MTTR Calculator
**URL:** https://calcrux.com/tools/manufacturing/mtbf-mttr-calculator
**What it does:** Free MTBF and MTTR calculator — compute mean time between failures, repair time, machine availability, failure rate λ, and downtime cost. Calculate free →
**Key outputs:** MTBF, MTTR, Machine Availability, Failure Rate, Total Downtime Cost, Shift Reliability
**Core formula:** MTBF Formula: MTBF = (Total Operating Hours − Total Downtime Hours) ÷ Number of Failures
**Q: What is MTBF?** MTBF (Mean Time Between Failures) is the average operating time between two consecutive unplanned breakdowns. A higher MTBF means the machine runs longer before failing, indicating better reliability.
**Q: What is MTTR?** MTTR (Mean Time To Repair) is the average time it takes to restore a machine after a failure. It covers detection, diagnosis, repair, and restart. A lower MTTR means your team recovers faster.
**Q: How is machine availability calculated from MTBF and MTTR?** Availability = MTBF ÷ (MTBF + MTTR). If your MTBF is 117 hours and MTTR is 3 hours, availability = 117 ÷ 120 = 97.5%. This is the theoretical fraction of time the machine is ready to run.
**Last updated:** 2026-06-07

### Takt Time Calculator
**URL:** https://calcrux.com/tools/manufacturing/takt-time-calculator
**What it does:** Free takt time calculator: compute available production time, required output rate, and cycle-to-takt ratio to keep your lean line on pace. Calculate free →
**Key outputs:** Takt Time, Available Time / Day, Required Output Rate, Takt Time (minutes), Cycle-to-Takt Ratio, Line Status
**Core formula:** Available time per day: Available Time = (Shift Duration − Break Time) × Number of Shifts
**Q: What is takt time in lean manufacturing?** Takt time is the available production time divided by customer demand — the maximum time allowed per unit to meet demand. It is the "drumbeat" of lean production, setting the pace for every workstation on the line. The concept originates from the Toyota Production System.
**Q: What is the takt time formula?** Takt Time = Available Time per Day ÷ Customer Demand per Day. Available time = (Shift Duration − Break Time) × Number of Shifts. The result is in seconds (or minutes) per unit.
**Q: How do you use takt time to balance a production line?** Compare each workstation's cycle time against takt time. Stations with cycle time above takt time are bottlenecks — redistribute their work content or add capacity. Aim for a cycle-to-takt ratio of 0.85–0.95 to leave a buffer for variation.
**Last updated:** 2026-06-07

### Production Capacity Calculator
**URL:** https://calcrux.com/tools/manufacturing/production-capacity-calculator
**What it does:** Free production capacity calculator — theoretical, effective, and net capacity across machines and shifts with OEE and scrap adjustments. Calculate free →
**Key outputs:** Theoretical Capacity, Effective Capacity, Net Output Capacity, Available Machine Hours, Capacity Utilization, Capacity Headroom
**Core formula:** Available Machine Hours: Machines × Hours/Shift × Shifts/Day × Working Days/Month
**Q: What is production capacity?** Production capacity is the maximum number of good units a facility can produce in a given period. It depends on machine count, shift hours, working days, cycle time, equipment efficiency, and scrap rate — all modeled together here.
**Q: What is the difference between theoretical, effective, and net capacity?** Theoretical capacity assumes 100% efficiency and zero scrap — the ceiling. Effective capacity applies your actual OEE (efficiency), giving a realistic output. Net capacity then deducts scrap, leaving only the good units you can ship.
**Q: How does OEE affect production capacity?** OEE (efficiency rate) scales your theoretical ceiling down to what is actually achievable. At 85% OEE, a line that could theoretically make 36,000 units/month will realistically produce 30,600 — a 5,400-unit gap that costs nothing to close with better uptime and run speed.
**Last updated:** 2026-06-07

### Safety Stock Calculator
**URL:** https://calcrux.com/tools/manufacturing/safety-stock-calculator
**What it does:** Free safety stock calculator — reorder point, holding cost, and days of cover from demand and lead time variability at any service level. Calculate free →
**Key outputs:** Safety Stock, Reorder Point, Annual Holding Cost, Days of Coverage, Cycle Stock (ROP base), Stockout Risk
**Core formula:** Combined Safety Stock Formula: Safety Stock = Z × √(LT × σd² + μd² × σLT²)
**Q: What is safety stock?** Safety stock is extra inventory held above your average needs to protect against demand spikes and supplier delays. It acts as a buffer so you can keep filling orders even when things do not go to plan.
**Q: How do you calculate safety stock?** The combined formula is: Safety Stock = Z × √(LT × σd² + μd² × σLT²), where Z is the service-level z-score, LT is average lead time, σd is daily demand standard deviation, μd is average daily demand, and σLT is lead time standard deviation.
**Q: What is a good service level for my business?** For standard consumer goods, 95% is a common starting point. Use 99% or higher for critical spare parts, medical supplies, or any item where a stockout causes significant cost or customer harm. Commodity items can run at 90%.
**Last updated:** 2026-06-07

---

## Ecosystem 4 — Startup & Business Intelligence

Runway, fundraising, equity, and growth tools for founders

### Startup Burn Rate Calculator
**URL:** https://calcrux.com/tools/startup/startup-burn-rate-calculator
**What it does:** Free startup burn rate calculator — compute gross and net burn, months of runway, bear/bull scenario stress-test, and 12-month cash outflow. Calculate free →
**Key outputs:** Gross Burn Rate, Net Burn Rate, Net Runway, Gross Runway, 6-Month Cash Outflow, 12-Month Cash Outflow, Runway Verdict, Bear Runway (burn +20%), Bull Runway (burn −20%)
**Core formula:** Gross burn rate: Gross Burn = Monthly Expenses − Non-Cash Charges (D&A)
**Q: What is startup burn rate and how is it calculated?** Burn rate is how much cash a startup consumes each month. Gross burn = monthly expenses − non-cash charges (D&A). Net burn = gross burn − monthly revenue. Net burn is the correct number for calculating runway because it reflects actual cash depletion.
**Q: What is the difference between gross burn and net burn?** Gross burn is total monthly cash expenses before revenue. Net burn subtracts revenue from gross burn — it's the real drop in your bank balance each month. A startup with 200K expenses and 80K revenue has a 120K net burn, not 200K.
**Q: How do you calculate startup runway?** Net runway = cash balance ÷ net burn rate. If you have 1.2M cash and burn 120K/month net, you have 10 months. Gross runway = cash ÷ gross burn — the worst-case if revenue stops. Both are important.
**Last updated:** 2026-06-07

### Unit Economics Calculator
**URL:** https://calcrux.com/tools/startup/startup-unit-economics-calculator
**What it does:** Free unit economics calculator — gross-margin LTV, CAC, LTV:CAC ratio with the 3× investor benchmark, churn sensitivity, and payback period. Calculate free →
**Key outputs:** Customer LTV, Customer CAC, LTV:CAC Ratio, CAC Payback Period, Avg Customer Lifetime, GM per Account / Month, LTV at Half Churn
**Core formula:** Customer Lifetime Value (LTV): LTV = (ARPA × Gross Margin %) ÷ Monthly Churn Rate
**Q: How do you calculate LTV:CAC ratio for a startup?** LTV:CAC = LTV ÷ CAC, where LTV = (ARPA × gross margin %) ÷ monthly churn rate and CAC = (sales + marketing spend) ÷ new customers. Using gross margin in LTV is essential — revenue-based LTV overstates the ratio.
**Q: What is a good LTV:CAC ratio for a startup?** 3× is the widely cited investor benchmark: LTV should be at least 3 times CAC. Below 1× you lose money per customer. Above 3× your unit economics are investor-grade. B2B SaaS with low churn often runs at 5–10× or higher.
**Q: What is CAC payback period and why does it matter?** CAC payback = CAC ÷ (ARPA × gross margin %). It is how many months until a customer pays back their acquisition cost. Under 12 months is strong; over 24 months strains cash because you need capital to fund growth.
**Last updated:** 2026-06-07

### SaaS Metrics Calculator
**URL:** https://calcrux.com/tools/startup/saas-metrics-calculator
**What it does:** Free SaaS metrics calculator — complete MRR waterfall, ending ARR, NRR, gross revenue retention, and Quick Ratio with investor benchmarks. Calculate free →
**Key outputs:** Net Revenue Retention (NRR), Ending MRR, Ending ARR, Net New MRR, Net New ARR, Gross Revenue Retention (GRR), MRR Churn Rate, SaaS Quick Ratio, CAC Payback Period
**Core formula:** Net Revenue Retention (NRR): NRR = (Starting MRR + Expansion MRR − Churned MRR − Contraction MRR) ÷ Starting MRR × 100
**Q: What is net revenue retention (NRR) and how is it calculated?** NRR = (Starting MRR + Expansion − Churned − Contraction) ÷ Starting MRR × 100. It measures how much of existing revenue you keep and grow. > 100% means expansion outpaces churn — best-in-class SaaS runs ≥ 120%.
**Q: What is a good NRR for a SaaS company?** ≥ 110% is strong; ≥ 120% is best-in-class (Snowflake, Datadog territory). 100% is break-even — the base isn't growing without new logos. Below 100% means churn outpaces expansion and revenue is declining from existing customers.
**Q: What is the difference between NRR and GRR?** NRR includes expansion (can exceed 100%); GRR ignores it (caps at 100%). GRR shows the "floor" — what you'd retain with no upsells. Strong SaaS has high GRR (> 90%) and high NRR (> 110%).
**Last updated:** 2026-06-07

### Equity Dilution Calculator
**URL:** https://calcrux.com/tools/startup/startup-equity-dilution-calculator
**What it does:** Free equity dilution calculator — pre/post-money valuation, investor stake, founder ownership, and option pool effect per funding round. Calculate free →
**Key outputs:** Post-Money Valuation, Investor Ownership, Founder Ownership (Post-Round), Founder Dilution, Founder Value (Pre-Money), Founder Value (Post-Money), Total Option Pool (Post-Round)
**Core formula:** Post-money valuation: Post-Money = Pre-Money Valuation + Investment Amount
**Q: How do you calculate equity dilution in a startup funding round?** Post-money = pre-money + investment. Investor % = investment ÷ post-money. Founder % after = founder % before × (1 − (investor% + option pool%) ÷ 100). This calculator does all three steps instantly.
**Q: What is pre-money vs post-money valuation?** Pre-money is the company's agreed value before investment. Post-money is pre-money + investment. A 5M pre-money with 1M raised gives a 6M post-money. The investor owns 1M ÷ 6M = 16.7%, not 20%.
**Q: What is the option pool shuffle?** The standard VC convention of creating the employee option pool pre-close — which means it comes from founders' equity, not the investor's. A 10% pool costs founders ~10 ownership points. Size it to a real hiring plan to minimise this cost.
**Last updated:** 2026-06-07

### Startup Break-Even Calculator
**URL:** https://calcrux.com/tools/startup/startup-break-even-calculator
**What it does:** Free startup break-even calculator — break-even units and revenue, contribution margin, CM ratio, margin of safety, and pricing sensitivity. Calculate free →
**Key outputs:** Break-Even Units, Break-Even Revenue, Contribution Margin, CM Ratio, Current Profit / Loss, Margin of Safety, Break-Even at +10% Price, Break-Even at −10% Price
**Core formula:** Contribution margin: CM = Selling Price − Variable Cost per Unit
**Q: How do you calculate the break-even point for a startup?** Break-even units = Fixed Costs ÷ Contribution Margin (price − variable cost per unit). Break-even revenue = Fixed Costs ÷ CM Ratio. At 10K fixed costs, 50 price, 20 variable cost: BE = 10K ÷ 30 = 333 units, or 16,667 revenue.
**Q: What is the contribution margin and why does it matter?** CM = price − variable cost per unit. It is what each sale contributes toward covering fixed costs and profit. A 30 CM on a 50 price = 60% CM ratio. Break-even is always fixed costs ÷ CM — low CM means higher break-even.
**Q: What is the margin of safety in break-even analysis?** Margin of safety = (current revenue − break-even revenue) ÷ current revenue. It shows how much revenue could fall before you hit a loss. A 20% margin of safety means a 20% revenue drop brings you to exactly break-even.
**Last updated:** 2026-06-07

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## Ecosystem 5 — Operational Financial Planning

Personal finance, business planning, and risk analysis tools

### SIP Calculator
**URL:** https://calcrux.com/tools/financial/sip-calculator
**What it does:** Free SIP calculator — annual step-up, inflation-adjusted returns and a year-by-year chart. Maturity value, total gains and real worth. Calculate free →
**Key outputs:** Maturity Value, Total Invested, Estimated Returns, Value in Today's Money, Wealth Multiple, Absolute Return, Returns Overtake Investment, Final-Year Monthly SIP, Step-Up Bonus
**Core formula:** SIP maturity value (annuity-due): FV = P × [ ((1 + i)^n − 1) ÷ i ] × (1 + i)
**Q: What is a SIP and how does a SIP calculator work?** A SIP invests a fixed monthly amount in a mutual fund at regular intervals. A SIP calculator projects the maturity value using the annuity-due formula: FV = P × [((1+i)^n−1)÷i] × (1+i). This one also shows returns separately, inflation-adjusted real worth, and your wealth multiple.
**Q: How is SIP maturity value calculated?** It uses the annuity-due formula: FV = P × [((1+i)^n−1)÷i] × (1+i), where P is monthly amount, i is monthly return (annual÷12), n is months. The ×(1+i) reflects contributions at month-start — the convention Groww and Zerodha use. 1,000/month at 12% for one year gives 12,809.
**Q: What is a step-up (or top-up) SIP, and how much does it add?** A step-up SIP raises your monthly investment by a set % each year, typically matching salary growth. Because higher contributions compound longer, a 10% annual step-up meaningfully boosts the final corpus. This calculator shows the exact step-up bonus versus a flat SIP of the same starting amount.
**Last updated:** 2026-06-07

### Lumpsum Calculator
**URL:** https://calcrux.com/tools/financial/lumpsum-calculator
**What it does:** Free lumpsum investment calculator — compounding frequency, effective APY, and inflation-adjusted returns with a year-by-year growth table. Calculate free →
**Key outputs:** Total Value, Invested Amount, Estimated Returns, Value in Today's Money, Wealth Multiple, Absolute Return, Effective Annual Yield, Returns Overtake Investment, Compounding Bonus
**Core formula:** Total (maturity) value: A = P × (1 + r/n)^(n × t)
**Q: What is a lumpsum calculator and how does it work?** A lumpsum calculator estimates what a single one-time investment grows into. Enter the amount, annual return, and years, and it applies A = P × (1+r/n)^(n·t) to produce your total (maturity) value. This one also shows returns, effective yield, inflation-adjusted worth, and wealth multiple.
**Q: How is lumpsum maturity value calculated?** It uses A = P × (1+r/n)^(n·t). 100,000 at 12% for 10 years with yearly compounding grows to 310,585 (100,000 × 1.12^10). More frequent compounding (n > 1) produces a slightly higher value because returns reinvest more often.
**Q: What compounding frequency should I choose?** For mutual funds, leave it Yearly — CAGR is already compounded annually, matching platforms like Groww. For FDs, bonds, or savings accounts that compound more often, pick the matching frequency. More frequent compounding raises your effective yield above the nominal rate.
**Last updated:** 2026-06-07

### Compound Interest Calculator
**URL:** https://calcrux.com/tools/financial/compound-interest-calculator
**What it does:** Free compound interest calculator — daily, monthly or yearly compounding, APY, total interest earned, and inflation-adjusted real value. Calculate free →
**Key outputs:** Final Balance, Interest Earned, Total Contributions, Value in Today's Money, Starting Principal, Effective Annual Yield, Compounding Bonus, Wealth Multiple, Time to Double, Interest Overtakes Contributions, Absolute Return
**Core formula:** Future value of the principal: A = P × (1 + r/n)^(n × t)
**Q: What is a compound interest calculator and how does it work?** Shows how money grows when interest earns interest. Enter balance, rate, term, compounding frequency, and contributions; it applies A = P(1+r/n)^(n·t) plus deposits' future value to return final balance, interest, APY, doubling time, and inflation-adjusted worth.
**Q: What is the compound interest formula?** The formula is A = P(1+r/n)^(n·t), where P is principal, r is the annual rate (decimal), n is compounding periods per year, t is years. A 10,000 balance at 5% monthly for 10 years gives ≈ 16,470. With contributions, it adds PMT × [((1+i)^N−1)÷i], where i=r/n and N=n·t.
**Q: How does daily compound interest differ from monthly or yearly?** More frequent compounding earns slightly more. The difference is the APY: 6% compounded yearly stays 6%, compounded daily it's ~6.18%. Pick yearly, half-yearly, quarterly, monthly or daily in this calculator and see the exact extra balance each frequency adds.
**Last updated:** 2026-06-07

### SIP vs Lumpsum Calculator
**URL:** https://calcrux.com/tools/financial/sip-vs-lumpsum-calculator
**What it does:** Free SIP vs lumpsum calculator — compare one-time vs monthly investing, see the growth gap, honest verdict, and when SIP beats lumpsum. Calculate free →
**Key outputs:** Which Wins, Monthly SIP Equivalent, Lump Sum Result, Flat SIP Result, Step-Up SIP Result, Lump Sum Lead, Step-Up Bonus, Lump Sum ÷ SIP, Winner in Today's Money, Lump Sum Returns, SIP Returns
**Core formula:** Lumpsum maturity: A = P × (1 + r)^t
**Q: SIP or lumpsum — which is better?** On the math, a lumpsum usually wins — every unit of money compounds for the full period. Vanguard found lump-sum investing beat spreading it out ~two-thirds of the time. A SIP's advantage is risk, not return: it protects against investing just before a fall and suits people investing from monthly income.
**Q: How does this SIP vs lumpsum calculator compare the two fairly?** It invests the same total both ways. The lumpsum puts the whole sum in today; the SIP spreads it as equal monthly instalments (monthly = total ÷ months), both valued at the same end date. Equal capital is what makes the comparison meaningful — many tools compare unequal amounts.
**Q: Why does the lumpsum usually win?** Time in the market. With a lumpsum, 100% is invested from day one; with a SIP, later instalments earn for less time. At a constant positive return, more time wins. For 1,200,000 at 12% over 10 years: lumpsum ~3,730,000 vs SIP's ~2,320,000.
**Last updated:** 2026-06-07

### SIP Goal Calculator
**URL:** https://calcrux.com/tools/financial/sip-goal-calculator
**What it does:** Free SIP goal calculator — find the monthly SIP to reach your target with inflation adjustment, current savings and annual step-up built in. Calculate free →
**Key outputs:** Required Monthly SIP, Future Cost of Goal, Total You'll Invest, Funded by Returns, Starting SIP With Step-Up, From Current Savings, Share From Returns, Feasibility, Cost of Waiting a Year, Goal in Today's Money
**Core formula:** Required monthly SIP (annuity-due): PMT = FV ÷ ( [ ((1 + i)^n − 1) ÷ i ] × (1 + i) )
**Q: What is a SIP goal calculator?** A SIP goal calculator works backwards from a target: you enter the corpus you want and by when, plus an expected return, and it solves for the exact monthly SIP. It adjusts the target for inflation, subtracts current savings, and can size a step-up SIP too.
**Q: How much SIP do I need to reach 10,000,000?** At 12%, reaching 10,000,000 needs about 10,009/month for 20 years, 20,017 for 15 years, or 43,041 for 10 years — horizon matters far more than the rate. If your 10,000,000 is in today's money, the inflated future cost (~32,000,000 in 20 years at 6% inflation) requires a proportionally larger SIP.
**Q: How is the required monthly SIP calculated?** It inverts the annuity-due formula: PMT = FV ÷ ([((1+i)^n−1)÷i] × (1+i)), where FV is the target, i is monthly return (annual÷12÷100), and n is months. Rearranging from the SIP formula, any monthly amount we return lands exactly on your target when fed back through a SIP calculator.
**Last updated:** 2026-06-07

### Retirement Calculator
**URL:** https://calcrux.com/tools/financial/retirement-calculator
**What it does:** Free retirement calculator — the corpus you need, whether your savings are on track, and the monthly investment to close the gap, adjusted for inflation.
**Key outputs:** Corpus Needed, Corpus Projected, Extra Monthly Investment, Shortfall, Surplus, Monthly Expense at Retirement, Corpus in Today's Money
**Core formula:** Expense at retirement: Future expense = current expense × (1 + inflation)^years to retire
**Q: What is a retirement calculator?** A retirement calculator works out how large a fund (corpus) you need to retire, by inflating your current expenses to retirement and funding them through your life expectancy. It also shows whether your savings are on track and the monthly investment to close any gap.
**Q: How much money do I need to retire?** Enough to fund your expenses, growing with inflation, for your whole retirement. A common shorthand is 25–30 times your annual expenses, but the exact corpus depends on inflation, your post-retirement return and how long retirement lasts — which this calculator computes precisely.
**Q: How is the retirement corpus calculated?** Your current monthly expense is inflated to your retirement year, then the calculator finds the lump sum that funds those inflation-growing withdrawals, earning the post-retirement return, until your planned age. It uses the inflation-adjusted (real) return to do this.
**Last updated:** 2026-06-15

### FIRE Calculator
**URL:** https://calcrux.com/tools/financial/fire-calculator
**What it does:** Free FIRE calculator — your FIRE number, the earliest age you can retire early, Coast and Barista FIRE, a year-by-year drawdown, and a Monte-Carlo test of whether the corpus survives. Works in today's money with India-real defaults.
**Key outputs:** FIRE Number, Earliest FI Age, Plan Survival Rate, Years to FI, Savings Rate, Coast FIRE Number, Barista FIRE Number, Lean FIRE Number, Fat FIRE Number, Drawdown Outcome
**Core formula:** FIRE number = annual expenses ÷ safe withdrawal rate (4% → 25×); years-to-FI grows net worth at the real return (1+return)/(1+inflation)−1 until it reaches that number.
**Q: What is my FIRE number?** Your FIRE number is your annual expenses divided by your safe withdrawal rate. At the classic 4% rate that is 25 times your annual spending; at a safer 3% it is about 33 times. The calculator computes it in today's money and shows leaner and fatter targets too.
**Q: How many years until I can retire early?** Your savings rate decides it more than your income — the share you invest. Someone saving 60% reaches independence far sooner than someone saving 15%. The calculator grows your net worth at the real return until it hits your FIRE number and reports the earliest age.
**Q: What is Coast FIRE?** Coast FIRE is the amount invested today that will grow to your full FIRE number by a target age with no further contributions. Once you hit it, you can stop investing for retirement and just cover your current expenses.
**Last updated:** 2026-07-06

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## Guides — Amazon FBA Fees (content cluster)

In-depth, sourced guides that explain seller costs and link to the matching calculators. Figures are Amazon US (USD) as of the 2026 rate card; other marketplaces mirror the same fee structure in local currency.

### Amazon FBA Fees Explained (pillar)
**URL:** https://calcrux.com/guides/amazon-fba-fees
**What it covers:** Every Amazon FBA fee for 2026 — the referral fee (percent of sale), the FBA fulfillment fee (flat per-unit pick-pack-ship), monthly storage (per cubic foot, higher in Q4), and the smaller 2024–26 fees (inbound placement, low-inventory-level, aged-inventory). Includes a worked example on a $25 product and tactics to reduce fees.
**Q: How much does Amazon FBA take per sale?** Roughly 25%–40% of the sale price for a typical small standard item — usually a 15% referral fee plus a flat fulfillment fee (~$3.42) and a few cents of storage, about $7–8 on a $25 sale before product cost. Bigger, heavier items pay more.
**Related tools:** Amazon FBA Profit Calculator, Amazon Referral Fee Calculator, Amazon Storage Fee Calculator

### Amazon Referral Fees by Category
**URL:** https://calcrux.com/guides/amazon-referral-fees
**What it covers:** The referral fee is Amazon's commission on each sale — usually 15%, ranging 8%–17% by category, with a $0.30 minimum, charged on item + shipping. Covers the category rate table and the tiered rules (e.g. Beauty/Health at 8% ≤ $10, 15% above).

### Amazon FBA Fulfillment Fees & Size Tiers
**URL:** https://calcrux.com/guides/amazon-fba-fulfillment-fees
**What it covers:** The flat per-unit fulfillment fee, set by size tier and weight (from ~$3.42 for small standard to $50+ oversize), the 2024 price-band adjustment, and why shrinking packaging to drop a tier is the highest-return fee optimisation.

### Amazon FBA Storage Fees & Aged Inventory
**URL:** https://calcrux.com/guides/amazon-fba-storage-fees
**What it covers:** Monthly storage per cubic foot ($0.78 Jan–Sep / $2.40 Oct–Dec for standard size), the Q4 spike, the escalating 181-day aged-inventory surcharge, and the low-inventory-level fee for understocking.
**Last updated:** 2026-07-09