What body fat percentage do you have with an 80, 90 or 100 cm waist?
Estimate your body fat percentage in seconds with the US Navy method — the most common tape-measure approach. You just measure your neck and waist (and hips, for women) plus your height. We give you the percentage, your category and, if you add weight, your fat and lean mass.
Sex
US Navy tape-measure estimate. Margin of error ±3-4% vs DEXA. Not a medical diagnosis.
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How is body fat calculated?
The US Navy method estimates body fat from body circumferences and height, using a formula validated against hydrostatic weighing. Men need neck and waist; women also need hips, because fat distribution differs enough that one equation cannot cover both. It is not a body scan: expect roughly 3-4 percentage points of error against a DEXA. What it is very good at is consistency — measured the same way each time, the trend it draws is reliable even when the absolute number is a little off, and the trend is what you actually act on.
Body fat percentage by waist size
Height and weight alone cannot tell you your body fat: the same weight can be muscle or fat. A tape measure gets much closer. Here is what the calculator gives a 1.78 m man with a 38 cm neck and a 1.65 m woman with a 33 cm neck and 98 cm hips, by waist circumference.
| Waist | Man 1.78 m · neck 38 cm | Woman 1.65 m · neck 33 cm · hips 98 cm |
|---|---|---|
| 75 cm | 7.9 % · athletes | 28.4 % · average |
| 80 cm | 12.4 % · athletes | 30.9 % · average |
| 85 cm | 16.4 % · fitness | 33.3 % · high |
| 90 cm | 20.1 % · average | 35.7 % · high |
| 95 cm | 23.6 % · average | 38.0 % · high |
| 100 cm | 26.7 % · high | 40.3 % · high |
| 105 cm | 29.7 % · high | 42.5 % · high |
| 110 cm | 32.5 % · high | 44.7 % · high |
Computed with the same function as the calculator. Source: US Navy formula (Hodgdon and Beckett, 1984) and American Council on Exercise categories. It is a tape-measure estimate, not a DEXA scan. These are reference ranges for healthy adults, not a diagnosis or individual advice.
FAQ
Can you calculate body fat from height and weight alone?
Not reliably: height and weight only give you BMI, which cannot tell muscle from fat. That is why this calculator uses a tape measure (US Navy method): a 1.78 m man with a 38 cm neck comes out at 12.4% body fat with an 80 cm waist and 26.7% with a 100 cm waist, even at the same weight.
What body fat percentage do I have with a 90 cm waist?
It depends on your height, your neck and, for women, your hips. A 1.78 m man with a 38 cm neck and a 90 cm waist comes out at 20.1%; a 1.65 m woman with a 33 cm neck, 98 cm hips and a 90 cm waist, at 35.7%. The chart above covers 75 to 110 cm.
What body fat percentage is healthy?
It depends on sex. In men, a fitness range sits around 14-17% and the healthy range roughly 10-20%; in women, around 21-24% for fitness and 18-28% healthy. Below about 5% in men and 12% in women is essential fat, and going near it is not a goal, it is a risk.
How do I measure the neck and waist properly?
Neck: just below the larynx, tape angled slightly downwards at the front. Waist: at navel height in men, at the narrowest point in women. Tape snug but not compressing, at the end of a normal exhale. Measure at the same time of day, ideally before eating.
Is the US Navy method reliable?
For tracking progress, yes — it is consistent and repeatable, which is what matters. For a precise absolute number, no method short of DEXA or hydrostatic weighing qualifies, and even those disagree with each other by a couple of points.
Keep reading
- Visceral fat: how to reduce it →
- How to lose belly fat →
- Measuring progress beyond the scale →
- BMI: what it is and where it fails →
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