About Us

CalorLab is a free, privacy-first calorie calculator for anyone tracking weight, building muscle, or just trying to eat the right amount. We translate the science of metabolism into a single clear number — and back it with the macros and a forecast you can actually use.

Why We Built It

Most calorie tools stop at "here is your number." But to make it work you also need to know your maintenance (TDEE), your goal-adjusted target, how that splits into protein, carbs and fat, and roughly where the scale will head over the next few weeks. CalorLab puts all of that on one page and runs everything locally — no uploads, no waiting, no accounts.

Our Principles

• Simplicity. Big clear numbers, not a wall of settings.
• Privacy by design. Calculations happen in your browser; your data never leaves your device.
• Honesty. Every value is an estimate, and we say so. We warn when a target looks too aggressive.
• Free, always. No paywalls, no sign-ups, no trial timers.

How It Works

Enter your age, gender, height, weight and activity level. The page's JavaScript estimates your BMR with the Mifflin-St Jeor equation, multiplies it by an activity factor for your TDEE, then subtracts or adds calories for your chosen goal. It calculates macro grams (protein at ~2 g/kg, fat at ~25% of calories, carbs for the rest), offers a 16:8 fasting window, and draws a 12-week weight projection. All of it runs on your device.

Who This Is For

Beginner dieters learning their baseline, gym-goers dialing in a lean bulk or cut, and anyone who wants a quick, trustworthy daily target without a spreadsheet.

Get in Touch

Questions, bugs or feature ideas? Visit our Contact page — we reply to every message.