Body Fat % Calculator (US Navy Method)

How to use

1. Pick sex and units.
2. Measure neck (below the larynx, snug), waist (at the navel for men; narrowest point for women), and hip (widest point — women only).
3. Enter measurements and read the body fat %, lean mass, and fat mass.

Frequently asked questions

How accurate is this vs DEXA?

Studies show ~3-4% standard error for most adults. Less accurate for very lean athletes (underestimates) and very obese individuals (overestimates). Good enough to track progress over time.

Why do women need a hip measurement?

The female formula uses waist + hip - neck because women carry more fat below the waist. The male formula uses only waist - neck because men's fat distribution is more torso-centric.

Where exactly do I measure?

Neck: just below the larynx. Waist (men): at the navel. Waist (women): at the narrowest point. Hip (women): at the widest point including the buttocks. All measurements snug but not compressing skin.

What's a healthy body fat %?

Roughly: men 10-20%, women 18-28% for general fitness. Athletes are typically lower (6-13% men, 14-20% women). Below 4% (men) / 12% (women) is dangerous.

Related tools