Body Fat % Calculator
Estimate your body fat percentage using the U.S. Navy method, Army method, or basic measurement method. Enter your measurements to get an accurate estimate with health range interpretation.
Health Disclaimer: This calculator uses the US Navy method to estimate body fat percentage. Results are approximations and should not be used as a medical diagnosis. Body fat percentage varies with age, ethnicity, and fitness level. Consult a healthcare professional for accurate body composition analysis and before making any health decisions.
Quick Facts
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How to Use This Calculator
- Select your sex (male or female) — the formula uses different measurement sites.
- Choose your unit system: Imperial (inches) or Metric (centimeters).
- Enter your height, neck circumference, and waist circumference.
- If female, also enter your hip circumference.
- Click Calculate to see your estimated body fat percentage, category, and lean mass.
The Formula
Male: %BF = 86.010 x log10(waist - neck) - 70.041 x log10(height) + 36.76. Female: %BF = 163.205 x log10(waist + hip - neck) - 97.684 x log10(height) - 78.387. (US Navy Method, using circumference measurements.)Frequently Asked Questions
The US Navy method is accurate to within 3-4% of hydrostatic (underwater) weighing for most people. It is less accurate for very muscular individuals or those with unusual fat distribution patterns. It is the standard method used by the US military for fitness assessments.