About Us

FitCalc is a small collection of free nutrition and body-composition calculators built for people who train, diet or simply want to understand the numbers behind their food.

Why we built it

Most calorie calculators either bury the maths behind a signup wall or dump a single number on screen with no explanation. We wanted the opposite: a tool that gives a result immediately, shows the formula behind it, and leaves you knowing more than when you arrived.

Every calculator runs entirely in your browser. Your height, weight and measurements never travel to a server, we keep no accounts, and there are no paywalls.

How we calculate things

• Resting metabolism uses the Mifflin-St Jeor equation, the current standard in sports nutrition, with Katch-McArdle offered when body fat is known.
• Activity adjustments follow the standard multipliers used by the Academy of Nutrition and Dietetics.
• Body fat is estimated with the US Navy circumference method or the Deurenberg equation.
• Reference ranges follow published guidance rather than magazine folklore.

Our editorial promise

We write in plain English, cite the equations we use, and update pages when better evidence appears. Nothing here is sponsored content, and no product placement influences the numbers you see.

Results are educational estimates. They do not replace advice from a doctor or registered dietitian — please read our disclaimer for the full statement.

Get in touch

Found a number that looks wrong, or want something added? We answer every message and genuinely use the feedback to prioritise new calculators. Start at the contact page.

Results come from published population equations and are estimates only — they are not medical advice. See our disclaimer.

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