Body Fat Calculator
Estimate your body fat percentage with the U.S. Navy tape-measure method, plus fat mass, lean mass and your fitness category.
About the Body Fat Calculator
Body fat percentage is a better measure of health and fitness than weight alone. This body fat calculator uses the U.S. Navy method, which only needs a tape measure: measure your neck and waist (and hips for women) and get an estimate within a few percent of lab tests.
How to Use the Body Fat Calculator
- Measure your neck just below the larynx, and your waist at the navel. Women also measure the widest part of the hips.
- Enter the measurements together with your height and weight.
- Press Calculate to see your body fat, fat mass and lean mass.
Formula and How It Works
Men: body fat % = 495 ÷ (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450. Women: 495 ÷ (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450, with all measurements in centimetres.
Frequently Asked Questions
What is a healthy body fat percentage?
According to the American Council on Exercise, “fitness” levels are 14–17% for men and 21–24% for women, and “average” is 18–24% for men and 25–31% for women.
How accurate is the Navy method?
It is usually within 3–4% of a DEXA scan when measurements are taken carefully. Measure in the morning, relaxed, without pulling the tape tight.
Results are estimates for general information and are not medical or veterinary advice. Please speak to a qualified professional about your own situation.