Body Fat Percentage Calculator
US Navy method with lean body mass and category.
How to Use
- Choose Metric (cm) or Imperial (in).
- Select gender and enter height, neck and waist (plus hip for women).
- Enter weight to also see lean and fat mass.
Calculation Method
US Navy circumference method (measurements in inches):
- Men: %BF = 86.010·log₁₀(waist − neck) − 70.041·log₁₀(height) + 36.76
- Women: %BF = 163.205·log₁₀(waist + hip − neck) − 97.684·log₁₀(height) − 78.387
Lean Body Mass = weight × (1 − %BF). Categories follow ACE body-fat norms.
Source: U.S. Navy circumference method; ACE body-fat categories
Examples
≈ 18% body fat → Fitness range
≈ 25% body fat → Fitness range
Frequently Asked Questions
It is typically within 3–4% of a DEXA scan when measurements are taken carefully at the right anatomical points.
For men, at the navel; for women, at the narrowest point. Keep the tape snug and level.
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Health & Fitness Disclaimer
The health and fitness calculations provided are estimates only and should not replace professional medical advice. Individual health needs vary based on medical conditions, medications, personal goals and activity level. Consult with a healthcare provider, registered dietitian, or certified fitness professional before making significant changes to your diet or exercise routine. Not medical advice.
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Last updated: May 24, 2026