How the US Navy method works
This method estimates body fat percentage using circumference measurements (neck, waist, and — for women — hips) combined with height, based on a formula developed for the US Navy as a fast, equipment-free alternative to skinfold calipers or hydrostatic weighing.
Getting an accurate measurement
Measure neck just below the larynx, waist at the narrowest point (or navel level for men), and hips at the widest point, using a flexible tape pulled snug but not compressed. Measuring at the same time of day, on skin rather than over clothing, improves consistency between readings.
General body fat percentage ranges
For men, roughly 6-13% is often considered athletic, 14-17% fit, 18-24% acceptable, and 25%+ obese. For women, ranges run higher due to essential fat differences: roughly 14-20% athletic, 21-24% fit, 25-31% acceptable, and 32%+ obese. These are general guides, not medical thresholds.
Frequently asked questions
How accurate is this compared to a DEXA scan? The US Navy method typically has a margin of error of around 3-4 percentage points compared to DEXA — good for tracking trends, less precise for exact clinical values.
Why is my BMI and body fat result different? BMI only considers weight and height, while body fat percentage reflects actual composition — the two can disagree meaningfully for muscular or very lean individuals.