About AlphaCalcs

AlphaCalcs is a free collection of calculators for the questions people actually type into a search bar: what a mortgage really costs, whether a body weight sits in a healthy range, what 18% of a restaurant bill comes to.

How the calculators are built

Each tool is written in plain JavaScript and runs entirely inside your browser. There is no account, no upload and no database. When you close the tab, the figures are gone.

Formulas come from published, citable sources: amortisation follows the standard annuity formula, BMI follows the WHO definition, resting metabolic rate uses the Mifflin-St Jeor equation. Where a formula has known limits, the page says so instead of hiding it.

How the site is funded

AlphaCalcs is free to use and paid for by advertising. Ads are clearly labelled and never dressed up as results or recommendations. We do not sell your inputs, because we never receive them.

Corrections

If a calculator gives an answer you can show to be wrong, tell us on the contact page with the inputs you used. Corrections are made quickly and the page notes the date it was last reviewed.