Body Fat Calculator

Estimate your body fat percentage with the U.S. Navy circumference method — just a tape measure needed. See your category, fat mass, and lean body mass.

Estimated Body Fat
Category
Fat mass
Lean body mass
Method
U.S. Navy circumference formula

The U.S. Navy Body Fat Method

The U.S. Navy method estimates body fat percentage from a few tape-measure circumferences — neck and waist for men, plus hips for women — along with your height. It's the most popular at-home method because it needs no special equipment and is reasonably accurate for most people, typically within 3–4% of a clinical measurement.

Men: 86.01×log10(waist − neck) − 70.041×log10(height) + 36.76

Body Fat Categories

The American Council on Exercise classifies men as essential fat (2–5%), athletes (6–13%), fitness (14–17%), average (18–24%), and above average (25%+). For women the ranges are higher: essential (10–13%), athletes (14–20%), fitness (21–24%), average (25–31%), and above average (32%+). Women naturally carry more essential fat for hormonal and reproductive health.