The US Navy method estimates body fat percentage from your height and a few circumference measurements. It needs only a tape measure, and for most people it lands within a few percentage points of lab methods.
For consistent results, measure at the same time of day, keep the tape level and snug but not tight, and take the average of several readings.
Formula
Men: BF% = 495 ÷ (1.0324 − 0.19077·log₁₀(waist − neck) + 0.15456·log₁₀(height)) − 450
Women: BF% = 495 ÷ (1.29579 − 0.35004·log₁₀(waist + hip − neck) + 0.22100·log₁₀(height)) − 450. All measurements in centimetres.
Body fat ranges
Men: essential 2–5%, athletes 6–13%, fitness 14–17%, average 18–24%, obese 25% and above. Women: essential 10–13%, athletes 14–20%, fitness 21–24%, average 25–31%, obese 32% and above.
Frequently asked questions
How accurate is the Navy body fat method?
It is a reasonable estimate for most people but can be off by 3–4 percentage points, especially for very muscular or very lean people.
Where should I measure my waist?
Men measure horizontally at the navel. Women measure at the narrowest part of the waist, and the hips at their widest point.
Last updated · Calculations checked by automated tests· Editorial policy