The U.S. Navy method
This calculator estimates body fat from circumference measurements instead of a scale or special equipment. For men it uses height, neck and waist; for women it also uses the hip measurement. The formulas were developed for military fitness screening and give a reasonable estimate for most adults.
How to measure correctly
- Height: stand straight without shoes.
- Neck: measure just below the larynx, with the tape sloping slightly down to the front.
- Waist: for men, at the navel; for women, at the narrowest point. Relax and do not pull in your stomach.
- Hip (women): around the widest part of the buttocks.
Typical ranges
For men, about 6–13% is athletic, 14–17% fit, 18–24% average. For women, about 14–20% is athletic, 21–24% fit, 25–31% average. Some body fat is essential for health, so very low values are not a goal for most people.
Limits
Tape-measure methods can be off by several percentage points. Use the result to track changes over time rather than as an exact value, and speak to a health professional for a precise assessment.
Frequently asked questions
How accurate is it?
Usually within a few percentage points for most adults, but less accurate for very muscular or very lean people.
Why is the hip measurement only for women?
The Navy formula for women includes the hip circumference, while the men's formula does not.
Is this a medical test?
No. It is an estimate for information only.