Health

Body Fat Calculator — US Navy Method, Free, No Upload

Estimate your body fat percentage using the US Navy circumference method — one of the most accurate tape-measure techniques available. Enter height, waist, neck, and (for women) hip measurements. Metric and imperial supported. Everything runs in your browser.

Frequently Asked Questions

How accurate is the US Navy method?
Studies show it estimates body fat within 3–4% of DEXA scan results for most people — more accurate than BMI and reliable without expensive equipment.
Where do I measure waist and neck?
Measure your waist at the narrowest point (near the navel), your neck just below the larynx, and for women, the widest part of the hips.
Is my data sent anywhere?
No. All calculations happen in your browser. Nothing is stored or transmitted.