Body Fat Calculator

Estimate your body-fat percentage using the US Navy circumference method — just a tape measure. See your body-fat category and share the result. Free, metric & imperial.

Measure at the narrowest neck, the navel for waist.

Enter your measurements

How to use the Body Fat Calculator

  1. 1

    Choose cm or inches and your sex.

  2. 2

    Measure and enter your height, neck and waist (plus hips for women).

  3. 3

    See your estimated body-fat percentage and category.

  4. 4

    Share your result.

Frequently asked questions

How accurate is the Navy method?

It's a solid, widely used estimate from body measurements. For clinical accuracy, a DEXA scan is the gold standard.

Where do I measure?

Neck below the larynx, waist at the navel, and (for women) hips at the widest point — keep the tape level and snug.

Is my data saved?

No — the calculation runs entirely in your browser.

Tips & discussion

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