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Body fat calculator
Estimate body fat percentage from tape measurements.
Quick answer
Measure your neck and waist (and hips for women) and enter your height. A man 175 cm tall with a 38 cm neck and 85 cm waist has about 17% body fat.
Estimated body fat
16.9%
- Fat mass
- 11.9
- Lean mass
- 58.1
A tape estimate can be several percentage points off. A general estimate, not medical advice. Talk to a doctor or dietitian about your own health.
How it works
The US Navy method estimates body fat from a few tape measurements instead of a lab scan.
Measure the waist at the navel, relaxed and breathing out, and the neck just below the larynx. Take each twice.
It suits tracking your own change over time better than comparing with other people.
The formula
- Men: 495 รท (1.0324 โ 0.19077 ร log10(waist โ neck) + 0.15456 ร log10(height)) โ 450
- Women: 495 รท (1.29579 โ 0.35004 ร log10(waist + hip โ neck) + 0.22100 ร log10(height)) โ 450
- All measurements in centimetres
A worked example
Man, height 175 cm, neck 38 cm, waist 85 cm: waist โ neck = 47, and the formula gives about 16.9% body fat.
Common questions
What is a healthy body fat percentage?
It varies with age and sex. Many sources put roughly 10 to 20% for adult men and 18 to 28% for adult women as healthy, but a doctor can advise you.
How accurate is the tape method?
It can be off by several percentage points. DEXA scans and other lab methods are more accurate.
Why are hips needed for women?
The equation for women uses hips because fat is distributed differently.
How often should I measure?
Every few weeks, at the same time of day and in the same way.