Body Fat Calculator
Calculate your body fat percentage with the US Navy method, based on simple body measurements — no calipers or special equipment needed.
How to use the body fat calculator
- Choose sex and enter your height.
- Measure the circumference of your neck (just below the larynx) and waist (at navel height), in centimeters.
- Women also enter hip circumference (widest point). The calculator shows body fat percentage and category.
How the body fat is calculated
The calculator uses the US Navy method, a recognized formula developed by the US Navy to estimate body fat without calipers or a DEXA scan:
Women: 495 ÷ (1.29579 − 0.35004 × log₁₀(waist + hip − neck) + 0.22100 × log₁₀(height)) − 450
The method uses circumference measurements instead of skinfold measurements, and has been shown to give a reasonably accurate estimate compared to more advanced measurement methods, especially for people of average build.
Frequently asked questions
Why do women need a hip measurement but not men?
The US Navy formula is sex-specific because fat distribution typically differs between men and women. The hip measurement improves accuracy for women, who often store more fat in the hip area.
Where should I measure my waist?
Measure around the narrowest part of your waist, usually at navel height, without pulling your stomach in.
What's considered a healthy body fat percentage?
This varies with sex and age, but for men 10–20% and for women 18–28% is generally considered a healthy normal range. Athletes are often lower.