Underwear size in figures

Sep 12, 2026

Short answer: Men's underwear is chosen by waist measurement taken where the waistband will sit. On most men that is just above the hip bone, not at navel height. When the size is right, the waistband lies flat without rolling.

Measure where the waistband sits

The measurement that counts is the circumference where the waistband will actually lie. On most men that is just above the hip bone. If you measure at navel height, you get a number that suits high waisted trousers but is too small for underwear. Use a soft tape and find the number in the size guide. See bamboo underwear for men.

How to measure

Stand relaxed and do not pull your stomach in. Place the tape around the body just above the hip bone, where the waistband usually sits. The tape should lie level all the way round and must not pull tight. Measure on bare skin. If you are unsure of the height, put on a pair you like and measure exactly where its waistband sits.

Why navel height gives the wrong number

The body is often narrower at navel height than a little lower, and many people pull their stomach in slightly when measuring. Both give a number smaller than what the waistband actually has to cover. The result is a size that feels tight and rolls, because it sits somewhere other than where it was measured.

Leg length follows the size

On long johns and tights, leg length follows the size and cannot be chosen separately. A larger size also gives a longer leg, and a smaller one a shorter leg. If your legs are long for your waist, that can be worth thinking about, but waist measurement should still decide, because the waistband has to sit right.

The waistband must not roll

If the waistband rolls down, the size is either too small or too big. A waistband that is too small is under too much tension and rolls down looking for a narrower place to sit. One that is too big has no grip and slides, so the fabric gathers and rolls. A waistband that fits lies flat all day.

Leg edges should follow the thigh

Besides the waistband, the leg edges should rest calmly on the thigh. If they ride up, the size may be too small or the fabric lacks room over the seat. If they stand away from the leg, the size is often too big. Leg edges that follow the thigh keep the underwear in place as you walk and sit.

Socks are chosen another way

Waist measurement is only for underwear. Socks are chosen by shoe size, and their size covers a span of sizes. So do not measure your waist when choosing socks, just use the shoe size you usually buy. See socks for men and women.

Wash so the waistband lasts

The waistband keeps its shape longest with low temperatures and drying without heat. Wash underwear gently and let it dry hanging. Avoid pulling hard on the waistband when taking it off. That way it still lies flat after many washes, and the size fits as it did at the start. See the men's range.