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Body fat % calculator

Estimate body composition from tape-measure circumferences using the U.S. Navy method.

Measure waist at the navel and neck just below the larynx, tape snug but not compressed.

Fat mass
Lean mass
Accuracy of the Navy method

This method has a margin of error of roughly ±3–4 percentage points against a DEXA scan, which remains the gold standard for precise body composition. Treat the result as a useful estimate for tracking trends over time, not a lab-grade measurement. Curious how you compare on the standard weight screen too? Try the BMI calculator.

For clinical-grade body composition analysis, ask your provider about a DEXA scan or bioelectrical impedance test.

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