Body Fat Calculator
Estimate body fat percentage, fat mass and lean mass from tape measurements.
Body fat %
16.9%
Fat mass
12.7 kg
Lean mass
62.3 kg
Category
Fitness
Estimate only — not medical advice. Tape measurements can vary and do not replace an assessment by a qualified health professional.
How to use Body Fat Calculator
- 01Choose metric or imperial, then enter your height, weight and sex.
- 02Measure your neck and waist — and hips if female — with a tape held snug but not tight.
- 03Read your estimated body fat percentage, fat mass, lean mass and category.
About Body Fat Calculator
The US Navy method estimates body fat from circumference measurements rather than skinfolds or a scan. It works because fat distributes predictably relative to frame size, and it is accurate to roughly three or four percentage points for most people — good enough to track change over time.
Body fat percentage tells you far more than BMI, which cannot tell muscle from fat. Typical healthy ranges are about 8-19% for men and 21-32% for women, with essential fat around 3% and 12% respectively. Measure at the same time of day, in the same posture, and watch the trend rather than any single reading.
Frequently asked questions
- How accurate is the Navy method?
- Usually within three to four percentage points of a DEXA scan, which is fine for tracking progress.
- Where exactly do I measure?
- Neck just below the larynx, waist at the navel for men and at the narrowest point for women, hips at the widest point.
- Why does it need different measurements by sex?
- Men and women store fat differently, so the formula uses hip circumference for women to stay accurate.
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