Estimate body fat percentage
Estimate body fat percentage from tape-measure measurements, using the US Navy method.
Uses the US Navy circumference method. Measure neck just below the larynx, waist at the navel, and (for women) hips at their widest point. Accuracy depends on measuring consistently.
Use a soft tape measure. Metric or imperial, whichever is easier to read.
The US Navy formula differs slightly for men and women.
A quick, tape-measure-only estimate. Not a substitute for a proper body composition scan.
Frequently asked
How accurate is the US Navy method?
It's typically within a few percentage points of more precise methods (like DEXA scans) for most body types, and is popular because it only needs a tape measure. Measuring consistently (same spot, same tension) matters more than the exact formula.
Where exactly should I measure?
Neck just below the larynx (Adam's apple), waist at the navel, and (for the female formula) hips at their widest point. Keep the tape snug but not compressing the skin.
Why am I seeing a validation message instead of a result?
The formula requires waist to be larger than neck (or waist+hip larger than neck, for the female formula). If your measurements don't satisfy that, double-check them for a typo or unit mismatch.
Is this medical advice?
No. It's a mathematical estimate for general informational purposes only, not medical advice. Consult a healthcare provider for an accurate body composition assessment.