FitCalcs
Free fitness & nutrition calculators. Free, instant, and no signup — pick a calculator to get started.
Reverse Diet Calculator
Coming off a diet? Get a week-by-week plan to raise calories safely and minimize fat regain.
Open calculator →Macro Calculator
Find your daily calories and macros — protein, carbs, and fat — for your goal.
Open calculator →Simple, accurate fitness math
FitCalcs gives you clear answers to the numbers questions that come up in training and nutrition — how many calories you burn, how much protein to eat, how to structure a reverse diet, and more. Every calculator is free, works instantly in your browser, and uses well-established formulas. No accounts, no fluff.