Free Calculators

Nine calculators, zero sign-ups.

Real formulas from peer-reviewed papers. No ads, no logins, no fluff — just type your stats, hit calculate, get your number. Bookmark whichever ones you like.

How to use these calculators

Pick the one that matches your question. Want to know how many calories you burn in a day? Try the TDEE Calculator. Setting up a fat-loss plan? The Daily Calorie Calculator and the Macro Calculator work hand-in-hand. Curious about your body composition? The Body Fat Calculator uses the same circumference method the US Navy has used for decades.

Every calculator runs entirely in your browser. Your numbers never leave your device, and every formula links back to its original published paper so you can verify the math yourself.

One honest note up front: these are estimates. Equations like Mifflin-St Jeor are accurate within roughly 10% for healthy adults — close enough for planning, not close enough to bet your health on. If you have a medical condition or you're way outside population norms, talk to a doctor or a registered dietitian.

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