Body Fat Calculator

Estimate your body fat percentage using the U.S. Navy circumference method.

Reviewed by the WorldCalcs team · Methodology · Last reviewed: June 2026

Height (cm)Neck (cm)Waist (cm)

Estimated body fat

18.4 %

U.S. Navy circumference method. Estimate only — not a diagnosis.

What is body fat percentage?

Body fat percentage is the share of your total body weight that is fat. It is often a better health indicator than weight alone because it separates fat from muscle, bone and water.

How it's calculated

This tool uses the U.S. Navy circumference method, which estimates body fat from your height and a few tape measurements (neck and waist, plus hip for women). Example: a man 180 cm tall with a 40 cm neck and 90 cm waist gets about 18.4 %.

All calculations happen in your browser. Nothing is sent, stored, or tracked.

Results are estimates and may contain errors — for general information only, not professional advice. Always verify before relying on them. Disclaimer

How to use

Pick metric or imperial, select sex, then enter your height and tape measurements. Body fat percentage updates instantly.

Measure with a flexible tape, keeping it level and snug but not compressing the skin. Take each measurement two or three times and use the average.

Frequently asked questions

How accurate is the U.S. Navy body fat method?+

It is a reasonable estimate for most people but less precise than methods like DEXA; measure carefully for best results.

Where do I measure my waist and neck?+

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

Why do women need a hip measurement?+

The female formula includes the hip circumference because body-fat distribution differs, which improves the estimate.

What is a healthy body fat percentage?+

It varies by age and sex; general fitness ranges are often cited around 10–20 % for men and 18–28 % for women.

References

Hodgdon JA, Beckett MB. U.S. Navy circumference-based body-fat equations, 1984.