About Calzeno

Calzeno provides free, accurate fitness and health calculators that help anyone understand and act on their body metrics — from BMI and calories to macros and body fat — without paywalls, sign-ups, or guesswork.

Our mission

Reliable health information should be free and easy to understand. We build simple, fast tools that turn a few measurements into clear, useful numbers, and we explain what those numbers mean and how to use them toward your goals.

How we calculate

Every calculator is built on established, peer-reviewed formulas used by clinicians and researchers, including:

• Mifflin–St Jeor equation for BMR and TDEE
• World Health Organization (WHO) classifications for BMI
• U.S. Navy circumference method for body fat percentage
• Robinson, Miller, Devine, and Hamwi formulas for ideal weight
• Acceptable Macronutrient Distribution Ranges (AMDR) for macros

Each calculator page links to the original sources so you can verify the methodology yourself. We review our formulas and content periodically to keep them current.

The Calzeno app

Beyond the web calculators, the free Calzeno app for iOS and Android helps you track calories and macros over time with barcode and photo-based food logging — turning the numbers from these calculators into daily habits.

A note on medical advice

Calzeno provides general educational estimates, not medical advice. Individual health needs vary, and our tools are not a substitute for professional diagnosis or treatment. Always consult a qualified healthcare provider or registered dietitian before making significant changes to your diet, exercise, or health routine.

Questions or feedback? Reach us via our LinkedIn page.