Free Ecommerce Seller Calculators & Tools
Ecommerce calculators are free online tools that help sellers work out profit, fees, ROAS, and inventory across Amazon, eBay, Etsy, Shopify, and Walmart. These free ecommerce calculators give you the same profit, fee, and inventory numbers that paid tools like Helium 10 and Jungle Scout charge for — with no account required. Run any Amazon FBA product through the profit calculator, compare seller fees across eBay, Etsy, Shopify, or Walmart before you list, and see your true margin after shipping and advertising costs. There are 20 tools covering every decision an ecommerce seller faces: when to reorder stock (EOQ), how hard your inventory is working (GMROI), whether your ad spend pays back (ROAS and PPC break-even), and how much a customer is worth over time (LTV:CAC). Four categories — Financial and Profitability, Inventory and Operations, Shipping and Logistics, and Ads and Marketing — all free, all instant, all in your currency.
Financial & Profitability
26 tools
Inventory & Operations
9 tools
Shipping & Logistics
2 tools
Ads & Marketing
13 tools
Showing all 50 tools
All 50 tools, grouped by category.
Financial & Profitability (26)
Amazon FBA Profit Calculator
Calculate your true Amazon FBA profit, margin, and ROI in seconds.
Profit Margin Calculator
All three P&L margins stacked in one view, with markup conversion — any currency.
Shopify Profit Calculator
Shopify profit after plan fee, processing and ads — and when to upgrade.
eBay Fee Calculator
Real eBay profit after all six fees — and store subscription break-even.
Etsy Fee Calculator
Real Etsy profit after all five fees — including the $10K Offsite Ads trap.
Selling Price Calculator
Pick your channel, set your target margin — get the exact price that nets it after real marketplace fees.
LTV CAC Calculator
LTV:CAC ratio, payback, and max CAC you can afford — on gross profit.
Discount & Promotion Profit Calculator
Before you run a discount, see the exact volume it needs and your safe floor.
Flipkart Fee Calculator
Your Flipkart settlement, profit, and every fee — by category, tier, and COD.
Contribution Margin Calculator
Calculate contribution margin per unit, CM ratio, and break-even point.
Product Profitability Calculator
Per-unit profit, margin, ROI, and monthly projections — fees and ads included.
Ecommerce Unit Economics Calculator
Contribution margin, break-even units, and monthly P&L from variable costs.
Amazon Referral Fee Calculator
Look up the exact Amazon referral fee for any category and selling price.
Amazon Storage Fee Calculator
Calculate Amazon FBA monthly and long-term storage fees by size tier and season.
Amazon IPI Score Calculator
Estimate your IPI score and find which factor is pulling it below 400.
Revenue Projection Calculator
Project 3–24 months of revenue from run rate, growth rate, and seasonality.
Markup Calculator
Find your selling price, markup %, or margin from any two inputs — any currency.
Break-Even Point Calculator
Find exactly how many units you need to sell before every extra sale is profit.
Ecommerce Conversion Rate Calculator
Calculate CVR, model revenue impact, and pinpoint your biggest funnel drop-off.
Dropshipping Profit Calculator
See your real dropshipping margin after ads, fees, shipping, and returns.
Landed Cost Calculator
Find your true per-unit import cost after freight, duty, and fees.
Customer Lifetime Value Calculator
Know what a customer is really worth — margin CLV, DCF CLV, and max CAC.
Product Pricing Calculator
Back-solve the selling price that hits your exact target net margin after all costs.
Ecommerce ROI Calculator
Calculate ROI, net margin, and payback period on your ecommerce investment.
Wholesale Pricing Calculator
Set wholesale prices that protect your margin and give retailers room to sell.
Return Rate Calculator
Calculate return rate, full return cost, and what a 1% reduction saves.
Inventory & Operations (9)
Economic Order Quantity (EOQ) Calculator
The EOQ calculator with orders/year, cycle days, and bulk discount check.
GMROI Calculator
Your GMROI, the ~3.2 retail benchmark verdict, and both levers that move it.
Amazon FBA Restock Calculator
Reorder point, days to reorder, and order quantity — no spreadsheets needed.
Inventory Turnover Calculator
Inventory turnover, DSI, and supply weeks — with a benchmark verdict.
Inventory Forecast Calculator
Project demand for 30–90 days with growth trend and seasonal adjustment.
Reorder Point Calculator
Calculate the exact inventory level to trigger your next order — no stockouts.
Inventory Carrying Cost Calculator
Calculate the true annual cost of holding inventory — all cost components.
Stock Coverage Calculator
See how many days your stock will last and whether a stockout is coming.
Dead Stock Calculator
Quantify dead stock costs and decide: liquidate, discount, or hold.
Shipping & Logistics (2)
Ads & Marketing (13)
Amazon Ads ROAS Calculator
True Amazon ad ROAS, break-even, and the max CPC you can profitably bid.
Break-Even ROAS Calculator
Minimum profitable ROAS for any channel — break-even, target, and ACoS.
Amazon PPC Break-Even Calculator
Break-even ACoS, max CPC, and min CVR — from your product economics.
Average Order Value Calculator
Calculate your AOV, get a free-shipping floor, and model what a lift is worth.
Cart Abandonment Calculator
Cart abandonment rate, lost revenue, and how much you can realistically recover.
Cost Per Acquisition (CPA) Calculator
Calculate CPA, break-even threshold, and whether each acquisition is profitable.
Marketing ROI Calculator
Measure marketing ROI from gross profit to LTV-adjusted return on spend.
Customer Retention Rate Calculator
Retention rate, churn rate, and the revenue value of keeping one more customer.
Ad Spend Scaling Simulator
Simulate profit, ROAS, and marginal return of scaling your ad budget.
Amazon ACOS Calculator
Calculate Amazon ACOS, break-even ACOS, and net profit from your ad campaigns.
Amazon TACoS Calculator
Calculate Amazon TACoS and see if ads build organic rank or just buy clicks.
Customer Payback Period Calculator
Find out how many months to recover your CAC — the metric that limits scale.
Marketing Efficiency Ratio (MER) Calculator
Measure blended MER across all channels — the true sign of marketing health.
Use cases
What you can do with these tools
- Calculate true Amazon FBA profit and net margin after all referral, fulfillment, and storage fees
- Compare seller fees across eBay, Etsy, Shopify, and Walmart before you list any product
- Measure ad efficiency with ROAS, break-even ROAS, and PPC break-even — free where competitors charge
- Plan stock smarter with EOQ reorder points, GMROI, inventory turnover, and safety stock tools
- Model unit economics, LTV:CAC ratio, and customer acquisition cost to scale profitably
- Run what-if pricing scenarios with the selling price, discount impact, and cart abandonment tools
Ecommerce Seller Operations — frequently asked questions
01Are these ecommerce calculators free to use?
Yes, every calculator in this category is completely free with no signup, account, or subscription required. Tools that competitors like Helium 10 and Jungle Scout put behind a paywall are free here, and you can use them as many times as you like.
02What is the Amazon FBA calculator?
The Amazon FBA profit calculator estimates your true profit per unit after all fees: referral fee, FBA fulfillment fee, storage fee, and your product cost and inbound shipping. Enter a selling price and costs to see net profit, margin, and ROI instantly.
03How do I calculate ecommerce profit margin?
Ecommerce profit = selling price minus product cost, marketplace fees, shipping, and advertising spend. The tricky part is marketplace fees, which vary by category and weight. Each Calcrux calculator handles fees automatically for Amazon, eBay, Etsy, Shopify, and Walmart.
04What is a good profit margin for an ecommerce product?
Most successful ecommerce sellers target a net margin of 15–30% after all fees, shipping, and advertising. Amazon FBA sellers often see 10–20% due to fulfillment fees. Use the profit margin calculator to check any product against these benchmarks.
05What is ROAS and what is a good ROAS for ecommerce?
ROAS (Return on Ad Spend) = revenue divided by ad spend. A 4:1 ROAS (earning 4 in sales per 1 spent on ads) is a common benchmark, but the ideal depends on your margins. The Calcrux ROAS calculator also shows your break-even ROAS for any product.
06Are these calculators better than Helium 10 or Jungle Scout?
Yes — and free. Calcrux covers Amazon FBA profit, margin, ROI, ROAS, break-even, EOQ, LTV:CAC, and GMROI calculations that Helium 10 and Jungle Scout include only in paid plans. Every tool here is free with no account, no usage cap, and no trial required.
07How accurate are the fee and profit calculations?
Very accurate. Marketplace fees are sourced from current published schedules for Amazon, eBay, Etsy, Walmart, and others. All engines are covered by automated tests, and rate data updates whenever platforms change their fee schedules.
08Which marketplaces and selling platforms do these tools cover?
Amazon FBA and FBM, eBay, Etsy, Walmart, and Shopify each have dedicated calculators. Platform-neutral tools for profit margin, pricing, ROAS, LTV:CAC, and inventory planning work for any online store or sales channel.
09Can I use these calculators in my own country and currency?
Yes. The tools detect your region automatically and support the US, UK, India, Australia, Canada, UAE, Singapore, Germany, and France — with the correct tax label (VAT, GST, or Sales Tax). You can switch country and currency at any time.
10How do I find the right ecommerce calculator?
Browse the four groups below: Financial and Profitability, Inventory and Operations, Shipping and Logistics, and Ads and Marketing. Use the search bar to filter by name or keyword, or open any calculator to see related tools.
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