Navy Body Fat Calculator
Estimate body fat percentage with the U.S. Navy circumference formula, then interpret your result for trend-focused tracking.
Measure at the same point each time for cleaner trend data.
Estimated body fat
18%
Category: Average
Fat mass
31.5 lb
Lean mass
143.5 lb
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Go to Body Fat Estimator →FAQ
How does this Navy body fat calculator work?
It applies the U.S. Navy circumference equations using height, neck, waist (and hip for women). Weight is optional for fat/lean mass estimates.
Which formula does this calculator use?
Men: %BF = 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76. Women: %BF = 163.205 × log10(waist + hip − neck) − 97.684 × log10(height) − 78.387. Inputs are converted to inches internally.
How should I measure to get better results?
Measure on bare skin or thin clothing, keep the tape level and snug, measure after a normal exhale without flexing, use the same landmarks every session, and average 2–3 readings.
Is this medical advice?
No. This is a fitness estimation and education tool. For diagnosis or treatment decisions, use qualified medical guidance.