US Navy method. Calculate body fat percentage, fat mass, and lean mass.
Free body fat calculator using the US Navy method. Calculate your body fat percentage, fat mass, and lean mass instantly. The US Navy body fat formula uses circumference measurements of your waist, neck, and height (plus hips for women) to estimate body fat percentage. This method is widely used by the military and fitness professionals as a reliable body composition assessment.
For men, the formula is: 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76. For women, it includes hip measurement: 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387. All measurements are in centimeters. The calculator also shows your fat mass and lean mass based on your total body weight.
Body fat ranges differ by gender. For men: Essential Fat (2–5%), Athlete (6–13%), Fitness (14–17%), Average (18–24%), and Obese (25%+). For women: Essential Fat (10–13%), Athlete (14–20%), Fitness (21–24%), Average (25–31%), and Obese (32%+). Maintaining a healthy body fat percentage supports cardiovascular health, energy levels, and overall fitness.