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Body composition · Free
Body Fat Estimator
The U.S. Navy tape-measure method — validated to within roughly ±3–4% of DEXA for most people. No AI, no calipers, just a tape measure and two minutes.
Estimated body fat
15.7%
Single-measurement accuracy is roughly ±3–4% vs DEXA.
Category
Fit
Based on widely used body-fat classification ranges.
Lean mass
84%
The rest of you — muscle, organs, bone, water.
How to measure
Neck: just below the larynx. Waist: at the navel, relaxed, not sucked in. Hips (female): at the widest point. Measure twice, use the average. Same setup, same time of day, and track the trend — not the daily number.