How the US Navy method works
The US Navy method estimates body fat from a few tape measurements. For men it uses height, neck and waist. For women it uses height, neck, waist and hips. The idea is simple: a larger waist compared with your neck and height points to more body fat.
Studies comparing it with lab methods generally put it within about 3 to 4 percentage points for most people. It is less reliable for very lean or very muscular people.
How to measure
- Use a soft tape and measure against bare skin, snug but not pressing in.
- Neck: just below the Adam's apple, tape level all the way round.
- Waist: men measure at the navel, women at the narrowest point. Breathe out normally first.
- Hips (women): around the widest part of the buttocks.
- Measure each spot twice and use the average.
Body fat categories
| Category | Men | Women |
|---|---|---|
| Essential fat | 2 to 5% | 10 to 13% |
| Athletes | 6 to 13% | 14 to 20% |
| Fitness | 14 to 17% | 21 to 24% |
| Average | 18 to 24% | 25 to 31% |
| Above average | 25% and over | 32% and over |
These ranges come from the American Council on Exercise. They describe where a result sits among adults and are not a diagnosis.
Common questions
How accurate is the Navy body fat method?
For most adults it lands within about 3 to 4 percentage points of lab methods such as DEXA. Careful, repeatable measuring matters more than anything else.
What is a healthy body fat percentage?
Using the American Council on Exercise ranges, 14 to 24% for men and 21 to 31% for women covers the fitness and average categories.
Why do women need a hip measurement?
Women tend to store more fat around the hips and thighs, so the women's formula adds hips to get a closer estimate.
How often should I measure?
Every two to four weeks is enough. Measure at the same time of day, ideally in the morning before eating.