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Body fat explained

Body fat percentage calculator

Estimate your body fat percentage with nothing but a tape measure. This calculator uses the US Navy method based on your circumference measurements and shows which category you fall into.

Calculate your body fat percentage

Measure with a tape: neck just below the larynx, waist at navel height, hips at the widest point.

What does your body fat percentage tell you?

Your body fat percentage indicates what share of your body weight consists of fat. It says more about your body composition than weight or BMI alone: two people at the same weight can have completely different body fat percentages depending on their muscle mass.

How the US Navy method works

The US Navy method estimates body fat from circumference measurements and your height. It was developed by the Naval Health Research Center and for most people lands within a few percentage points of more advanced measurements such as a DEXA scan.

How to measure accurately

The result is only as good as your measurements. Keep the tape snug without compressing the skin and measure at a consistent moment, for example right after waking up.

  • Neck: measure just below the larynx, with the tape sloping slightly forward.
  • Waist: men measure at navel height, women at the narrowest point of the waist.
  • Hips (women only): measure at the widest point of the glutes.
  • Take each measurement twice and use the average for a more reliable result.

The limits of this estimate

Every indirect measurement has a margin of error. Use the result to track your progress over weeks and months rather than as an absolute truth, and always measure the same way.