About Body Numbers

Our Mission

Body Numbers was created with a simple goal: provide everyone with free access to accurate, science-backed fitness calculators. Whether you're just starting your fitness journey or you're an experienced athlete, understanding your body's metrics is the foundation of reaching your goals.

We believe that knowledge should be free and accessible. Every calculator on our site uses well-established formulas from peer-reviewed research and exercise science literature. We don't hide results behind paywalls, require sign-ups, or collect your personal data.

How Our Calculators Work

All calculations are performed entirely in your web browser using JavaScript. Your data never leaves your device — we don't store, transmit, or collect any of the information you enter. This means you can use our calculators with complete confidence in your privacy.

Our calculators are built on established scientific formulas, including:

• Mifflin-St Jeor equation (1990) — for Basal Metabolic Rate calculation
• Harris-Benedict equation (revised 1984) — an alternative BMR formula
• Hodgdon & Beckett Navy method (1984) — for body fat estimation
• Karvonen method (1957) — for heart rate zone calculation
• Epley, Brzycki, and Lander formulas — for One Rep Max estimation
• Devine, Robinson, Miller, and Hamwi formulas — for ideal body weight
• Boer formula (1984) — for lean body mass estimation
• Cooper test (1968) — for VO2 Max estimation
• Wilks coefficient — for powerlifting strength comparison

Our Calculators

We offer 15 comprehensive calculators organized into four categories:

• Body Composition — BMI, Body Fat %, Ideal Weight, Lean Body Mass, Waist-to-Hip Ratio
• Calories & Nutrition — BMR, TDEE, Calorie Deficit/Surplus, Macro Calculator, Water Intake
• Strength & Performance — One Rep Max, Wilks Score, Pace Calculator
• Heart & Cardio — Heart Rate Zones, VO2 Max Estimator

Important Disclaimer

While our calculators use scientifically validated formulas, they are designed for educational and informational purposes only. They should not be used as a substitute for professional medical advice, diagnosis, or treatment. Individual results may vary based on factors like genetics, medical conditions, and body composition.

We strongly recommend consulting with a qualified healthcare professional, registered dietitian, or certified fitness trainer before making significant changes to your diet or exercise routine — especially if you have pre-existing health conditions.

Technology

Body Numbers is built with modern web technologies for the fastest possible experience. Our site is statically generated, meaning every page loads instantly. Calculator interactions are powered by lightweight JavaScript that runs entirely in your browser. We use no cookies for tracking and collect zero personal data.