About Numbrik

Numbrik is an independent website that makes free calculators for the questions people run into every day: how many hours they worked, what a loan will cost, what their GPA is, or how many millilitres are in a cup.

What we care about

• Accuracy. Every calculator shows its formula and a worked example, so you can check the answer yourself.
• Speed. Pages are small and results update as you type, on phones as well as computers.
• Local defaults. Currency, units and overtime rules follow the region you choose: the United States, Canada, Australia, the United Kingdom or the Netherlands.
• Privacy. Calculations happen in your browser. We don't ask you to sign up.

Sources and methods

Our calculators use standard, published methods. Examples include the US Fair Labor Standards Act overtime rule for the time card, the World Health Organization adult categories for BMI, the Mifflin-St Jeor equation for calorie needs, and the standard amortization formula for loans. Each page explains the method it uses and its limits.

Corrections

If you find a mistake or a rule that has changed in your country, please contact us. We review every report and update the page.

Last updated October 20, 2026.