Body Fat Calculator (US Navy Method)
Estimate body fat percentage using the US Navy method — just a tape measure and a few body measurements. Includes fitness category ratings and lean mass.
Body Fat (US Navy Method) Guide
How the Navy Method Works
The US Navy body fat method estimates body fat percentage using simple tape measurements and a formula. Developed for the US Navy to assess personnel without expensive equipment. Measurements needed: men: height, neck, and waist (at the navel). Women: height, neck, waist (narrowest point), and hip (widest point). The formula uses the ratio of these circumferences (the difference between waist and neck reflects abdominal fat). It's based on the relationship between body circumferences and fat dis
Measuring Correctly
Accurate measurements are crucial — small errors significantly affect the result. Neck: measure below the larynx (Adam's apple), with the tape sloping slightly downward to the front. Don't flex the neck. Waist (men): measure horizontally at the navel level. Relaxed, after breathing out. Don't suck in. Waist (women): measure at the narrowest point (usually above the navel). Hip (women): measure at the widest point of the buttocks/hips, horizontally. General tips: use a flexible (cloth or fibregla
Body Fat Categories
Body fat percentage categories (American Council on Exercise): men: essential fat: 2-5%. Athletes: 6-13%. Fitness: 14-17%. Average/acceptable: 18-24%. Obese: 25%+. women: essential fat: 10-13% (women need more essential fat for hormonal health). Athletes: 14-20%. Fitness: 21-24%. Average/acceptable: 25-31%. Obese: 32%+. Why women have higher healthy body fat: essential fat for women includes fat needed for hormonal and reproductive function. A healthy woman naturally carries more body fat than a
Using and Improving
What body fat % tells you: it's a better health and fitness indicator than weight or BMI alone. It distinguishes fat from muscle (BMI can't). Tracking it over time shows whether you're losing fat or muscle during weight changes. Reducing body fat: create a moderate calorie deficit (lose fat). Maintain protein intake (preserve muscle — see protein calculator). Resistance training (preserves/builds muscle while losing fat). Aerobic exercise (additional fat burning). Be patient — sustainable fat lo
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