Financial tools that grow your profits
Free, instant, no-login calculators for e-commerce sellers, freelancers, and startups. 100% private — nothing leaves your browser.
Profit Margin Calculator
E-commerceMarkup Calculator
E-commerceAmazon FBA Fees Calculator
E-commerceDiscount & Sale Calculator
E-commerceEtsy Fee Calculator
E-commerceShopify Fees Calculator
E-commerceeBay Fees Calculator
E-commerceSquare Fee Calculator
PaymentsStripe Fees Calculator
PaymentsPayPal Fees Calculator
PaymentsFreelance Hourly Rate
PaymentsVAT / Tax Calculator
PaymentsROAS / ROI Calculator
GrowthCustomer Acquisition Cost
GrowthBurn Rate Calculator
GrowthCompound Interest Calculator
GrowthFree Calculators Trusted by E-Commerce Sellers
Independent Shopify, Amazon, Etsy and eBay sellers use ProfitFlowTools to price products, audit marketplace fees, and protect margins. No accounts, no email capture — just the numbers you need before you hit publish on a listing or send an invoice.
Why Sellers Choose ProfitFlowTools
100% Private by Default
Every calculation runs in your browser. Your revenue, costs, and customer numbers never touch our servers — there are no servers in the loop.
Instant, No-Login Results
No signup wall, no free trial, no upsell. Land on a calculator, type your numbers, get a defensible answer in seconds.
Transparent Formulas
Every tool shows the formula, the variables, and authoritative references so you can verify the math — and explain it to a co-founder or accountant.
How Our Calculators Work
- 1
Pick a calculator
Browse by category or search by name to find the tool that matches your decision.
- 2
Enter your numbers
Type real values from your store, ad account, or invoice. Everything stays in your browser.
- 3
Read the result and formula
Get an instant answer plus the underlying formula, worked example, and citations.