About FitnessCalc
A free fitness calculator site built by a fitness enthusiast who got tired of ugly, slow, and inaccurate calculators.
The problem
Finding a good macro calculator online feels like it should be easy. There are hundreds of them. But most have one or more of these problems: they're plastered with so many ads the page is unusable on mobile, they require you to enter your email to see your results, they use outdated formulas (looking at you, Harris-Benedict), or the design looks like it was built in 2008.
I just wanted a clean, fast calculator that used accurate formulas and got out of my way. So I built one.
What we use
Every calculator on this site uses peer-reviewed formulas and recommendations. For BMR, we use the Mifflin-St Jeor equation (1990), which is the gold standard recommended by the Academy of Nutrition and Dietetics. For protein, we follow the ISSN position stand on protein and exercise. For creatine, we use dosing guidelines from the ISSN's comprehensive creatine review.
Our principles
No email gates
Your results are yours. We never require an email to see your numbers.
Science only
Every formula is sourced from peer-reviewed research or clinical guidelines.
Always free
These calculators will always be free. The site is supported by ads and affiliate partnerships.
Disclaimer
The calculators on FitnessCalc are for informational and educational purposes only. They are not a substitute for professional medical or nutritional advice. The estimates provided are based on validated equations but may not be perfectly accurate for every individual. Consult a qualified healthcare professional before making significant changes to your diet or supplement regimen, especially if you have a medical condition.
Questions or feedback? We'd love to hear from you.