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Body Fat Calculator

Estimate your body fat percentage with a tape measure, using the U.S. Navy formula. CraveSmart's body fat screen uses the same formula.

By Frank Cashio · Last reviewed

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Height

Just below the Adam's apple.

At the narrowest point.

At the widest point.

Estimated body fat

29.8%

How does the Navy body fat method work?

The U.S. Navy method estimates body fat from tape measurements and height. The U.S. Navy developed it to estimate body fat during fitness assessments.

Example: a woman who is 5 ft 5 in with a 13 in neck, 30 in waist, and 39 in hips has an estimated 29.8% body fat.

Men: 86.010 × log10(waist − neck) − 70.041 × log10(height) + 36.76

Women: 163.205 × log10(waist + hips − neck) − 97.684 × log10(height) − 78.387

All measurements in inches.

How to measure

  • Neck: just below the Adam's apple, with the tape sloping slightly down to the front.
  • Waist: men around the navel, women at the narrowest point.
  • Hips (women): around the widest part.
  • Stand relaxed, breathe out normally, and keep the tape snug but not tight.

It is an estimate. Lab methods like a DEXA scan can differ by several percentage points, so use it to track change over time.

Sources

  • Hodgdon JA, Beckett MB. Prediction of percent body fat for U.S. Navy men and women from body circumferences and height. Naval Health Research Center, Reports 84-11 and 84-29, 1984.

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Estimates for adults, not medical advice.