How the Navy body-fat formula actually works
The math behind circumference-based body composition estimates, decoded.
Body Composition — U.S. Navy Method
BMI hides where your weight sits. FatPulse uses the U.S. Navy circumference method to estimate your body fat from a tape measure alone — no scale, no clinic visit.
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Measuring…
Why it works
Research-grade body fat tests (DEXA, hydrostatic) cost time and money. The U.S. Navy circumference method uses age, sex and tape-measure figures to match clinical estimates within a few points — accurate enough to track monthly progress.
Generally yes for tracking body composition. BMI only compares weight to height and can't tell muscle from fat, so a lean athlete score can look "overweight". Body fat percentage measures what's actually fat versus lean tissue.
Within about 3 percentage points of DEXA for most people when measurements are taken correctly. Consistency matters more than precision — measure the same spot at the same time of day to see true trends.
A target of roughly 0.5–1% of body weight per week (a 250–500 kcal daily deficit) preserves muscle and is widely considered sustainable. Plan on losing about 0.5–1% body fat per month as a realistic benchmark.
Essential levels are about 2–5% for men and 10–13% for women. Athletic ranges run 6–13% (men) and 14–20% (women); acceptable zones are roughly 18–24% (men) and 25–31% (women).