Body Fat Calculator
Measure your neck and waist (and hips if you're a woman) and enter your height to estimate body fat percentage.
Your details
Result
Body fat
19.8%
Average
- US Navy circumference method. Tape-measure estimates can be off by several percentage points; use it to track change.
Good to know: A tape-measure estimate can be off by several percentage points. Use it to track change, not as an exact figure.
Please note: General estimate for information only. This is not medical advice, diagnosis or treatment, and it may not suit your age, health, medication or pregnancy. Never use it to make a medical decision. Talk to a doctor or other qualified health professional about your own situation, and in an emergency call your local emergency number.
About this tool
Estimate body fat percentage with the U.S. Navy circumference method from height, neck and waist (and hip for women), with category and lean mass.
Formula
Uses logarithms of circumference ratios: men use waist − neck vs height; women use waist + hip − neck vs height — converted to body density and then to a fat percentage.
Reference values
- Essential fat: 2–5% men, 10–13% women
- Athletes: 6–13% men, 14–20% women
- Acceptable: 18–24% men, 25–31% women
Questions people ask
How do I measure correctly?
Measure the neck below the larynx, the waist at the navel for men and the narrowest point for women, and hips at the widest point. Keep the tape level and snug.
How accurate is the Navy method?
It is a reasonable estimate but less accurate than clinical methods such as DEXA scans.
What is a healthy body fat percentage?
It varies by age and sex. Ask a health professional for a range that suits you.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
Spotted a mistake? Tell us and we'll check it. How we check our calculators