Kind Margin

Pricing and tax maths for freelancers and small businesses

Ten free calculators for setting prices, checking profit, planning loans and savings, and handling GST and VAT. Each one shows its formula, and the tax pages show where their rates come from.

Try one: margin and markup

Pricing and invoicing

Pick your currency. The maths is the same in every country.

Margin and markup calculatorTurn a cost into a price, or check the profit on a price you already charge.Works anywhere
Break-even calculatorHow many sales it takes to cover your fixed costs, with an optional profit target.Works anywhere
Freelance hourly rate calculatorWork back from the income you want to the hourly and day rate you need to charge.Works anywhere
Sales tax and VAT calculatorAdd tax to a price or take it back out of a total, at any rate you type in.Works anywhere
Invoice generatorFill in a clean invoice and print it or save it as a PDF. No account needed.Works anywhere

Loans and savings

With year-by-year breakdown tables.

Country tools

Local tax rates built in, checked on 10 October 2026.

How these tools are made

Every calculator runs in your browser, with no sign-up and nothing uploaded. Each page explains the formula in plain words and works through an example, so you can check the result by hand. Tax rates come from official government sources, which are linked on each page with the date they were last checked. More on the about page.