About us

About FitCalc

FitCalc started with a simple frustration: the numbers people find online are either wrong, vague, or copied from one site to the next without anyone checking them — and the calculator never shows its working.

Ask the internet for your TDEE and you will get answers 400 kcal apart, both stated with equal confidence, neither saying which equation it used or which activity multiplier it picked. Ask how much protein you need and you will get 0.8 g/kg, 1.6 g/kg and 2.2 g/kg — all correct for different people, none of them saying which person. Ask for a marathon pace and you will get a number with no mention of the formula behind it.

FitCalc does it differently. Every calculator on this site shows its formula: Mifflin-St Jeor for BMR and TDEE, the Compendium of Physical Activities MET values for calories burned, Epley and Brzycki for one-rep-max, Riegel for race-time prediction, and the 1.6–2.2 g/kg evidence range for protein. Every result is labelled an estimate, because formulas describe population averages and individual bodies differ. You can read exactly how we work in our Editorial Policy.

What we do

FitCalc has two parts. The first is 32 free tools: TDEE, BMR, calorie, maintenance, weight-loss and bulk calculators, BMI and body fat, macro and protein calculators, pace calculators for 5K to marathon, one-rep-max for bench, squat and deadlift, and more. Every tool runs entirely in your browser — nothing you type is sent to a server, and there is no sign-up.

The second part is in-depth guides: TDEE and maintenance calories, BMR, BMI, calories burned by activity, running pace, one-rep-max, macros and protein, each one 1,200+ words, written to answer the real questions people ask — not to pad a page with keywords. The guides are being written topic by topic, and every one is checked against published sources before it goes live.

What we will never do

We will never present an estimate as a fact. A formula result is a starting point, not a measurement of your body — and every page on this site says so. We will never recommend a calorie target below the safety floors: 1,200 kcal/day for women, 1,500 kcal/day for men, without medical supervision. We will never claim medical, dietetic or coaching credentials we do not have. And we will never sell your data — there is no account to create and nothing to sell. Read the Disclaimer and the Privacy Policy for the full picture.

Who is behind FitCalc?

FitCalc is a small, independent project run by people who train and got tired of bad fitness maths. We are not doctors, dietitians or coaches, and we do not pretend to be — that is exactly why every page on this site cites its sources and tells you to check with a professional before acting on a number. Our job is to make the published numbers easy to use and honest about their limits. If you spot a mistake, or a number you think is wrong, please tell us on the Contact page. We would rather fix a page than defend it.

Thank you for using FitCalc — and may your next PR be a real one. The TDEE Calculator is a good place to start.