Free tools built on science, not subscriptions.
FitnessCalc exists to give everyone access to the same high-quality fitness math that personal trainers, dietitians, and sports scientists use every day — completely free, with no sign-up required.
We believe that knowing your TDEE, your ideal protein intake, or your heart rate training zones shouldn't require a subscription or an app download. Good information should be accessible to everyone.
Every calculator on FitnessCalc is based on peer-reviewed research and widely validated formulas used in the fitness and sports medicine fields. We clearly note which formula each calculator uses so you can verify the source.
Examples include:
FitnessCalc tools are for informational and educational purposes only. Results are estimates based on population averages and validated formulas — individual variation exists and is expected. These calculators are not a substitute for advice from a qualified physician, registered dietitian, or certified personal trainer.
Before beginning any new diet or exercise program, consult with a qualified healthcare professional, especially if you have any pre-existing medical conditions.
We review and update our calculators regularly to ensure they reflect current best practices in sports science and nutrition research. If you notice an error or have a suggestion for a new calculator, please reach out via our contact page.
All calculations are performed locally in your browser. We do not collect, store, or transmit any of the personal or health data you enter into our calculators. See our Privacy Policy for full details.