About HOD Calc

HOD Calc brings together 300 free calculators in 13 categories: money, work, health, cooking, dates, maths, science, studies, business, games, code and conversions. Our goal is simple: give you the right answer in seconds, with a clear explanation of the method.

How we build our tools

Every calculator relies on a public, recognised formula (loan formula, official tax scales, standard medical or physics formulas). The method is explained under each tool, with a worked example. Scales that change every year (taxes, contributions, allowances) are reviewed regularly and flagged as estimates.

Your data stays with you

All calculations run in your browser. The values you enter are never sent to our servers. Your favourites and history are stored on your device only.

Who we are

HOD Calc is published by HOD Group, in Belgium. The site is free and funded by advertising.

Found a mistake or have an idea?

Write to us at contact@hod-group.com: every message is read, and many of our tools come from visitors' suggestions.