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Body Fat Calculator
Estimate your body fat percentage with the US Navy circumference method — just a tape measure, no calipers. Get your number and category instantly, then see what actually moves it.
Measure relaxed, with a flexible tape: neck below the larynx, waist at the navel.
How to measure
Use a flexible tape and stay relaxed — don’t suck in. Measure your neck just below the larynx, your waist at the navel, and (for women) your hip at the widest point. The method combines these with your height to estimate the fraction of your weight that is fat. Take each measurement twice and average for consistency.
Questions
- How does the US Navy method work?
- It estimates body fat from body circumferences — neck and waist for men, plus hip for women — together with your height. No calipers or scales needed, just a flexible tape measure.
- How accurate is it?
- It is typically within about 3–4% of a DEXA scan for most people — good enough to track your own trend over time, but not an exact clinical figure. Measure the same way each time for the most reliable comparison.
- What is a healthy body fat percentage?
- Rough ACE ranges: men 6–13% athletic, 14–17% fitness, 18–24% average; women 14–20% athletic, 21–24% fitness, 25–31% average. Some essential fat is necessary, and very low levels carry their own health risks.
- Is this medical advice?
- No. This is a general fitness estimate, not medical or clinical advice. If you have a medical condition or any history of disordered eating, talk to a doctor or qualified professional.
This calculator gives a general fitness estimate, not medical advice. If you have any history of disordered eating, please don’t use a body-composition tool — talk to a doctor or qualified professional.