Body Fat Calculator – U.S. Navy Method
Estimate your body fat percentage using the U.S. Navy circumference method. All you need is a flexible tape measure.
How to measure correctly
- Use a flexible, non-stretch tape measure.
- Measure first thing in the morning, before eating or drinking.
- Keep the tape parallel to the floor and snug — but never digging in.
- Record each measurement twice and average the two for accuracy.
Body fat percentage chart
| Category | Men | Women |
|---|---|---|
| Essential fat | 2 – 5% | 10 – 13% |
| Athlete | 6 – 13% | 14 – 20% |
| Fitness | 14 – 17% | 21 – 24% |
| Average | 18 – 24% | 25 – 31% |
| Obese | ≥ 25% | ≥ 32% |
Common questions
How accurate is the U.S. Navy method?
It is one of the more accurate field methods, with typical error of ±3–4% versus DEXA scans, when measurements are taken correctly with a flexible tape. It is significantly more accurate than visual estimates or BMI.
What body-fat percentage should I aim for?
For health, men typically aim for 10–20% and women for 18–28%. Athletes train at lower percentages but going below 6% (men) or 14% (women) for extended periods can disrupt hormones.
Why do women's measurements include the hips?
Women carry more body fat in the hips and thighs than men, so the formula adds the hip circumference to better capture lower-body fat distribution.
Should I use this or a DEXA / BIA scan?
If you have access to a DEXA scan, use that — it is the gold standard. The U.S. Navy method is a free, in-the-mirror alternative that is consistent enough to track changes over time.