About this site

What you will find here

Calculators for everyday questions: what a trip costs in fuel, what your BMI is, and more. Every calculator also shows how the answer is reached: the explanation updates step by step with your input.

Who makes this

This site is our own project: we build and maintain it ourselves. There is no company behind it.

How we calculate

Every calculator has its own built-in tests that run again with every change. The calculation happens in your own browser. Results are estimates; please also read the note below each result.

There are no live connections to external sources. Fixed numbers, such as a rate or a limit, are part of the calculator itself, and where possible we name the source. How we build and check our calculators is explained on the How we work page.

What 'used more than … times' means

Below the title of a calculator you may see how often it has been used. That number counts the visits in which someone got a result from that calculator: at most once per visitor per day, without bots, across all languages and up to yesterday. It is rounded down and only appears from 1,000. How we count is explained on the privacy page.