Free Online Calculators
for Every Business

Calcrux is a free online business calculator platform with 78+ tools for ecommerce sellers, manufacturers, startup founders, and investors. Every calculator runs instantly in your browser — covering 9 countries and 9 currencies — with no account, no paywall, and no limit.

78+ free calculators across five domains: ecommerce (Amazon FBA, Shopify profit, eBay fees), financial planning (SIP, compound interest, lump sum), manufacturing (OEE, MTBF/MTTR, takt time), India business (salary, income tax, HRA, EPF), and startup analytics (burn rate, LTV/CAC, equity dilution). Every tool runs free in your browser.

Yes — every calculator is completely free, with no account, no email, and no credit card required. All calculations run in your browser and your data never leaves your device.

9 markets are supported: US, India, UK, Australia, Canada, UAE, Singapore, Germany, and France. Calcrux auto-detects your country on arrival and adapts currency, tax labels, and number formatting automatically — you can override it any time via the region picker.

Highly accurate. Each formula cites a named standard: ISO 22400 for OEE, IEC 60050-191 for MTBF/MTTR, APICS for inventory, EPFO circulars for EPF, Income Tax India slabs for salary, and official Amazon/eBay fee schedules for marketplace tools. Sources are listed in each tool's Formula section.

Calcrux specialises in business operations where those tools are general-purpose. Each tool includes domain benchmarks, smart insights, and formulas verified against professional standards — not textbook approximations. We also deliver features that paid tools like Helium 10 and Jungle Scout charge for, free.

Calcrux offers 50+ free ecommerce calculators with no paywalled features — Amazon FBA profit, eBay fees, Shopify margin, Etsy fees, ACoS, TACoS, dropshipping profit, LTV/CAC, and more. Every calculation uses official fee schedules, not estimates, so your margin figures are accurate.

Yes — every calculator is designed mobile-first. Inputs stack cleanly on small screens, touch targets meet accessibility minimums, and results update in real time as you type — no submit button needed.

9 currencies are supported: USD, INR, GBP, EUR, AUD, CAD, AED, SGD, and more. Calcrux auto-detects your country and converts all monetary outputs to your local currency automatically. You can switch manually any time via the region picker.

Rates update whenever official sources change. Amazon fee schedules are sourced from Seller Central, India tax slabs follow Finance Act 2025, and every update is version-stamped with an effective date. Each tool displays a "last updated" date so you can see exactly how fresh the data is.

Yes — Calcrux has a full India Business suite: in-hand salary with PF and professional tax deductions, income tax comparison under old and new regimes, HRA exemption calculation, EPF corpus projection, and freelancer tax under Section 44ADA. All tools use Finance Act 2025 slabs.

Calcrux is used by ecommerce sellers to calculate Amazon FBA profit and marketplace fees, by manufacturers to measure OEE and equipment reliability, by investors to project SIP and lump-sum returns, by founders to model burn rate and runway, and by Indian professionals to compute salary and income tax — all free, no sign-up.