Body Fat Percentage Calculator (US Navy Method)
Estimate your body fat percentage, fat mass (kg), and lean body mass (kg) from tape-measure waist, neck, and height measurements.
Informational health estimates only
Outputs from this utility are based on population-level peer-reviewed formulas (WHO, Mifflin-St Jeor, US Navy, Devine) and are intended for educational wellness screening—not medical diagnosis or clinical treatment. Consult a qualified physician or registered dietitian for personalized guidance. Read our full Platform & Medical Disclaimer.
How the Body Fat Percentage Calculator (US Navy Method) works
Estimate your body fat percentage, fat mass (kg), and lean body mass (kg) from tape-measure waist, neck, and height measurements. Below is the exact mathematical or algorithmic model used by this body metrics utility, along with its key operating assumptions.
US Navy Equation using log₁₀(waist − neck) and log₁₀(height) for males; log₁₀(waist + hip − neck) for females.Step-by-step workflow
- Select your clinical reference standard or biological sex and enter height, weight, or activity metrics in the Body Fat Percentage Calculator (US Navy Method).
- The physiological model computes US Navy Equation using log₁₀(waist − neck) and log₁₀(height) for males; log₁₀(waist + hip − neck) for females. and maps your score against established reference bands.
- Use the target range and daily macro/hydration breakdown as an educational baseline alongside professional medical guidance.
Worked example & key advantages
Measure neck and navel waist circumference in centimeters to track fat loss even when scale weight plateaus.
Why use this Body Fat % tool
- Includes both Asian-Indian (ICMR) and WHO global BMI cutoffs alongside Mifflin-St Jeor and US Navy equations.
- Translates raw metabolic numbers into actionable daily calorie, protein-per-meal, and hydration targets.
- Runs privately in your browser with no account sign-up or health-data tracking.
Important Assumptions & Scope
- Take measurements against bare skin without pulling the tape tight.
Frequently Asked Questions — Body Fat %
Clear answers to common questions about methodology, edge cases, and privacy.
Why track body fat percentage alongside BMI?
BMI cannot distinguish between fat mass and muscle mass. A muscular person may have an 'Overweight' BMI while maintaining a healthy 14% body fat level.
Are results from the Body Fat Percentage Calculator (US Navy Method) a substitute for medical advice?
No. The Body Fat Percentage Calculator (US Navy Method) implements peer-reviewed population equations for general wellness education and fitness screening. Always consult a physician or registered dietitian for clinical guidance.
How often should I recalculate my metrics in the Body Fat %?
Recalculating every 4 to 8 weeks—or whenever your body weight, training volume, or lifestyle activity level changes significantly—helps keep your nutrition and wellness targets aligned.