Daily Figures Edition No Sign-Up • No Tracking • Free Forever Vol. XII — No. 204
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Fitness — Body Composition

Body Fat Calculator

Enter a few tape measurements to estimate your body fat percentage by the U.S. Navy method.

Filed by The Statistics Desk  |  Method: U.S. Navy circumference formula
women only
Body fat
—
U.S. Navy tape estimate.
Readout
Category—
Fat mass—
Lean mass—
Method—
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Enter your figures above to see the step-by-step working.
Educational estimate — a tape method, not a DEXA scanEverything computed client-side — nothing leaves this page

How the Body Fat Calculator Works

The U.S. Navy method estimates body fat percentage from a few tape-measure circumferences instead of calipers or a scan. It is popular because it needs no special equipment and is reasonably accurate for most people — the same method the Navy uses for its body composition standards.

Measure your height, neck and waist (and, for women, the hips) with a flexible tape, then the formula combines them on a logarithmic scale to estimate the percentage of your body that is fat. Men use waist minus neck; women add the hip measurement. Enter your body weight too and the calculator splits it into fat mass and lean mass.

Men: %BF = 495 ÷ (1.0324 − 0.19077 log(waist−neck) + 0.15456 log(height)) − 450

Frequently Asked Questions

How accurate is the Navy body fat method?

For most people it lands within about 3–4 percentage points of a DEXA scan, which is good for a tape measure. It can be off for very lean or very muscular individuals, but it is excellent for tracking change over time.

Where exactly do I measure?

Measure the neck just below the larynx, the waist at the navel for men and at the narrowest point for women, and the hips at the widest point. Keep the tape snug and level, and measure without holding your breath.

What is a healthy body fat percentage?

Broadly, fit ranges are about 10–20% for men and 18–28% for women, with athletes lower. Essential fat — the minimum to function — is around 3–5% for men and 10–13% for women.

More From The Desk

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