Health & Fitness

Body Fat Calculator

U.S. Navy method (approximate).

Sex Height (cm) Neck (cm) Waist (cm) Hip (cm, female)

Educational estimates only. Not medical, legal, tax, or financial advice.

Guide: Body Fat Calculator

Applies Navy regression formulas to estimate body fat percent from tape measurements.

Measure per the instructions, enter values in the selected units, then calculate. Results are approximate.

Uses sex-specific Navy equations based on circumference ratios and log terms (see official documentation for exact formulas).

If inputs align with a typical fit profile, you may see a mid-teens to twenties percent estimate depending on sex and measurements.

How accurate is this?

Useful for trends, not a gold standard. DEXA or hydrostatic tests are more accurate but costly.

Why measure at the same time of day?

Waist and bloating fluctuate; consistency reduces noise.

Can athletes use this?

Very muscular builds can skew some circumference methods; interpret cautiously.