How to measure your underwear size (jockstraps, briefs and boxers)

Underwear sizes aren’t standard. A medium from one brand can fit like a small from another, and many styles are cut on the snug side. The fix is easy: measure yourself once, then compare your numbers with the size chart on each product instead of guessing from the letter on the label.

What you need

• A soft tape measure (or a piece of string and a ruler).
• Underwear you’re wearing, or nothing at all, so the tape sits on skin.
• A mirror, to check the tape is level all the way round.

How to measure your waist

• Stand up straight and breathe out normally. Don’t suck in.
• Wrap the tape around where your underwear waistband actually sits, usually just below your belly button and above your hip bones. That’s lower than your jeans size suggests.
• Keep the tape level and snug, but not tight. You should be able to slide a finger under it.
• Read the number in centimetres and inches. That’s your underwear waist.

Tip: Your jeans size isn’t your underwear size. Jeans sizes are often vanity-sized and sit at a different point on your body, so always measure.

How to measure your hips

Some charts also list hips. Stand with your feet together and wrap the tape around the fullest part of your bum, keeping it level. Briefs, trunks and boxer briefs need room here; jockstraps and thongs mostly don’t.

Waist or hips? Even the big brands disagree

Brands don’t all measure the same way. Fruit of the Loom says to measure slightly below your natural waist, where you normally wear your pants. Tommy John says men’s underwear sits at the waist, so measuring your hips is unnecessary. Nike says that if your waist and hip measurements point to different sizes, go by your hips. The safe move: measure both, then follow each brand’s own chart.

How to read a size chart

• Find your waist measurement in the chart’s range for each size.
• If you’re inside one range, that’s your size.
• Check whether the chart is for your body or for the garment laid flat. A flat measurement is the relaxed waistband, which stretches when worn, so it can look smaller than your waist.
• Look at the fabric. Cotton with spandex stretches; mesh and lace have less give; latex and leather-look styles have almost none.

When you’re between sizes

Jockstrap fit, specifically

A jockstrap has three parts that need to fit: the waistband, the pouch and the two leg straps. The waistband should sit flat without rolling. The pouch should hold everything without gaping or squeezing. The straps should run under your cheeks and lift them, without cutting in at the sides. If the straps dig in but the waistband fits, try a style with wider straps rather than a bigger size. Our jockstrap guide goes deeper on styles.

Common sizing mistakes

• Measuring over jeans or a thick waistband.
• Pulling the tape tight. You’ll end up a size too small.
• Assuming every brand fits the same. Measure once, then check every chart.
• Ignoring the fabric. Stretchy cotton forgives; lace and mesh don’t.

Gays+ writes these guides and sells underwear, including some of the styles linked here. Every product page has its own size chart, and unworn items in their original packaging can be returned within 30 days of delivery.

Tip: Know your size? We compared prices, sizes and returns at 10 underwear stores, us included.

Sources

1. Fruit of the Loom: size guide
2. Tommy John: underwear size chart
3. Nike: underwear size and fit