About Calculatoo
Calculatoo is a collection of free online calculators for money, health, home, work, science and everyday questions.
Free, with no account
Every calculator is free to use and needs no sign-up. The site may show advertising to cover its costs.
Your numbers stay with you
Calculations run in your browser: what you type is not sent to us or stored. The site only counts how often each calculator is used, without identifying anyone.
How the results are checked
Each calculator uses a standard formula, explained on its page with a worked example. The way the calculators are built and tested is described on the How we calculate page.
Contact
Found a mistake, or missing a calculator? Use the feedback form at the bottom of any calculator page. Every message is read.