How to measure your waist
Wrap a tape measure around your midsection at the level of your navel, keep it horizontal all the way around, and pull it snug without compressing the skin. Read it at the end of a normal breath out. Measure twice and use the average. Most fitness and military body-fat tests use this navel-level measurement.
Where exactly to measure
The right spot depends on the method you are using, and getting it wrong is the most common reason two people measure the same body differently:
- Navel level (most methods): the Army waist-to-height standard and the men's US Navy body-fat method both measure around the abdomen at the belly button.
- Narrowest point (some women's methods): the US Navy body-fat method measures women at the smallest part of the waist, usually just above the navel.
Whichever you use, keep the tape parallel to the floor the whole way around. A tape that rides up in the back reads too small.
| Use | Where to measure |
|---|---|
| Army standard (waist-to-height) | At the navel |
| Navy body fat, men | At the navel (abdomen) |
| Navy body fat, women | Narrowest point of the waist |
| General health (WHtR) | At the navel |
How to hold the tape
- Stand relaxed, feet together, arms at your sides. Do not suck in.
- Bring the tape around bare skin, not over clothing.
- Level it front and back, check in a mirror.
- Pull it snug, then ease off until it sits against the skin without denting it.
- Breathe out normally and read the number at the end of the breath.
Common mistakes
- Sucking in. It changes the number and is not how the standards are measured.
- Measuring over clothes. Even a t-shirt adds a fraction of an inch that skews the result.
- Tape not level. Riding up in the back is the classic error and reads low.
- One reading only. Take two or three and average them; if they differ by more than half an inch, measure again.
What your waist measurement is used for
That one number feeds several tests. It is the whole of the Army's current body-composition standard, a waist-to-height ratio that must stay under 0.55. It is also a key input to the US Navy body-fat estimate. Enter your measurement into either calculator to see where you land.