Free Body Fat Calculator

Estimate your body fat percentage using the U.S. Navy method based on body measurements.

inches
inches
inches

Body Fat Percentage

17.5 %

Lean Mass Percentage82.5 %

Body Fat Percentage vs Waist Circumference

U.S. Navy Body Fat Formula (Male)

Body Fat % = 86.010 x log10(waist - neck) - 70.041 x log10(height) + 36.76

All measurements are in inches.

Body Fat Categories (Male)

CategoryBody Fat % Essential Fat2-5% Athletes6-13% Fitness14-17% Average18-24% Obese25%+

Example Calculation

A male with a 34-inch waist, 15-inch neck, and 70 inches tall.

  1. 01Waist - Neck = 34 - 15 = 19 inches
  2. 02log10(19) = 1.2788
  3. 03log10(70) = 1.8451
  4. 04Body Fat = 86.010 x 1.2788 - 70.041 x 1.8451 + 36.76
  5. 05= 110.0 - 129.2 + 36.76 = 17.5%

Frequently Asked Questions

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