Estimate your body fat percentage using the US Navy circumference method. Enter your height, weight, and body measurements to get an estimate of body fat % and lean body mass.
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Obese | 25%+ | 32%+ |
Body fat percentage expresses fat mass as a proportion of total body weight. It distinguishes between two people of identical weight and height whose composition differs completely — information BMI cannot provide.
| Category | Men | Women |
|---|---|---|
| Essential fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Above average | 25%+ | 32%+ |
Women carry more essential fat than men for physiological reasons, which is why the categories differ and why male ranges should never be applied to women.
Tape-measure methods, such as the US Navy formula, use circumference measurements at the neck, waist and hips alongside height. They are free and reasonably consistent, but they infer composition from proportions rather than measuring fat directly.
More accurate approaches — DEXA scanning, hydrostatic weighing, air displacement — require specialist equipment and cost money.
Every field method carries meaningful error, commonly several percentage points. Bioelectrical impedance scales are particularly sensitive to hydration, recent food, recent exercise and time of day, which is why readings can swing noticeably within a single day.
For that reason, trend matters far more than any single figure. Measure under the same conditions each time — same time of day, similar hydration, same method — and watch the direction over weeks rather than reacting to one reading.
This is general information, not medical advice. Discuss changes to diet or training with a healthcare professional, particularly if you have any underlying condition.