How to Measure Yourself for Underwear: A Step-by-Step Guide

Guessing your size from memory is how most fit problems start. Bodies change a little over time, and every brand cuts things slightly differently anyway. Taking a fresh measurement is one of the best ways to land on the right size, especially when you're trying a brand for the first time. It only takes a couple of minutes, and it's one part of the bigger picture we walk through in our guide to underwear and lingerie sizing.

What's the Fastest Way to Measure Yourself for Underwear?

Grab a soft measuring tape and wrap it around your natural waist the narrowest part of your torso, which sits above your hips but isn't always at navel height. Write the number down in both cm and inches. If the brand you're buying from includes a thigh measurement on its chart, measure that too. Then match your numbers to that specific brand's chart, rather than the letter size you normally buy.

Important: underwear doesn't always sit at your natural waist. Low-rise styles sit lower, closer to your hips. If a brand's size chart shows where it wants you to measure, follow that diagram over a generic method. It'll give you a more accurate result for that specific product.

What You'll Need

You don't need anything fancy for this:

• A soft, bendy measuring tape (the kind used for sewing works well)

• A mirror, if you want to check the tape is sitting level

• A pen and paper, or your phone's notes app, to write your numbers down

• Underwear or light clothing on, rather than jeans or anything bulky

If you don't have a soft tape lying around, a piece of string works too — just measure the string against a ruler afterwards.

Step-by-Step: How to Measure Your Waist

Waist is one of the most commonly used measurements across underwear size charts, so it's worth getting right.

1. Stand up straight, in a relaxed position — don't hold your stomach in or push it out.

2. Find your natural waist. This is the narrowest part of your torso, somewhere between your ribs and your hips. It can sit above or below your belly button depending on your body, so don't assume the navel is always the right spot.

3. Wrap the tape around your waist, keeping it level all the way round.

4. Pull it snug, but not tight. You should be able to fit one finger under the tape comfortably.

5. Read the number where the tape meets itself, and write it down in both cm and inches.

If you're not sure whether you've found your natural waist, bend gently to one side — the crease that forms is usually close to it. And if a brand's chart specifies a different spot to measure, go with theirs.

Step-by-Step: How to Measure Your Hips

Hip measurement matters for a lot of styles, especially anything low-rise or hip-hugging.

1. Stand naturally, with your feet together or slightly apart, whichever feels normal for you.

2. Wrap the tape around the fullest part of your hips and bottom — this is usually a few inches below your waist.

3. Keep the tape level all the way around, not angled up or down at the back.

4. Pull it snug without squeezing in, and write down the number.

For Boxer Briefs and Trunks: Check If a Thigh Measurement Is Needed

Not every brand asks for a thigh measurement, but some do, particularly for close-fitting boxer briefs and trunks where the leg opening sits snug. Check the brand's own size chart first — if it lists a thigh measurement, here's how to take it:

1. Stand with your weight even on both feet.

2. Wrap the tape around the fullest part of one thigh, just below where your leg meets your body.

3. Keep the tape level and snug, but not tight.

4. Write the number down. If one thigh measures noticeably bigger than the other, use the larger number.

If your thigh measurement lands in a different size bracket than your waist, don't automatically size up — going bigger can leave the waistband too loose. Check the brand's own fit notes first. If the leg opening still feels tight even once your waist size is correct, a different cut or style might suit you better than sizing up.

Common Mistakes When Measuring Yourself

A few small habits throw off the numbers more than people realize:

• Measuring over jeans or thick clothing. This can add a couple of centimeters without you noticing.

• Pulling the tape too tight. It should sit snug, not squeeze — a tight tape gives you a smaller number than your real size.

• Measuring at the wrong spot. Your natural waist is the narrowest point of your torso, not wherever your usual jeans happen to sit — those can vary a lot depending on the cut. Measure the actual narrowest point, or wherever the brand's chart tells you to.

• Holding your stomach in. It feels natural to do this, but it makes the number less accurate. Stand relaxed instead.

• Only measuring once. If your first and second measurement come out different, take a third and go with the middle number.

What to Do With Your Numbers

Once you've got your waist (and hip or thigh, if needed), the next step is matching them to a size chart — ideally the specific brand's own chart rather than a general one. Letter sizes like S, M, and L don't mean the same thing everywhere, so your numbers are far more reliable. Our guide on men's underwear size chart breaks down how these measurements line up across Australia, the UK, the US, and Europe, if you're shopping from an international brand.

When Your Measurements Don't Match a Size Label

It happens more often than you'd think — you measure carefully, and you're still stuck between two sizes, or a size that "should" fit ends up feeling wrong. A few things can explain this:

• Brands use their own sizing and grading standards, so the same measurement can land in a different size bracket depending on the brand. This is sometimes down to vanity sizing, but it's usually just a difference in how a brand builds its pattern — we cover it in our guide on why sizes vary between brands.

• Fabric matters. A stretchy fabric can feel fine even if your measurement is right on the size boundary, while a stiffer fabric might need you to size up.

• Style changes the fit. As covered above, boxer briefs fit differently to loose boxers, even at an identical waist measurement.

If you've measured properly and you're still getting an odd fit, it's usually not you — it's the garment. Our fit troubleshooting guide covers the most common problems and how to fix them, whether that's chafing, a tight waistband, or a leg opening that digs in.

Measuring Someone Else (If You're Buying for Them)

Sometimes you're not measuring yourself at all — maybe you're picking up underwear for a partner, or helping a family member who can't easily do it themselves. A few tips make this easier:

• Ask, if you can. It sounds obvious, but a quick text asking for a waist measurement saves a lot of guesswork.

• Check a pair they already own and like. Most underwear has the size printed on an inside label. If it fits them well, that's a great starting point.

• If you're between sizes, check the brand's guidance first. Some people prefer a closer fit, and sizing up isn't automatically the safer choice — it can cause bunching or slipping in close-fitting styles. If there's no clear guidance, the larger size tends to be the more comfortable pick for everyday, non-fitted styles.

• Keep the receipt handy. Most stores are happy to exchange for a different size, so this takes the pressure off getting it exactly right the first time.

Frequently Asked Questions

How often should I measure myself again?

About once a year is a good habit, or any time your usual size starts to feel different. Weight changes, even small ones, can shift your numbers enough to matter.

Should I measure over my skin or over clothes?

Bare skin or thin, close-fitting clothing gives the most accurate number. Thick or loose clothing can add a centimeter or two without you realizing.

What if my waist and hip measurements point to two different sizes?

Check the brand's own chart first, since the right call can depend on the specific style. As a general starting point, the larger measurement is often the safer bet for close-fitting cuts, but it's not a fixed rule.

Can I trust the size I've always bought, instead of remeasuring?

Not always. Even if your body hasn't changed, brands sometimes update their size charts, and every brand has small differences anyway. A quick remeasure once in a while is worth the effort, especially before trying a brand for the first time.

Does it matter what time of day I measure?

Measurements can shift very slightly through the day, so try to measure at a similar time if you're comparing numbers over weeks or months. Being consistent matters more than picking a specific "correct" time.

Do I need to measure every single time I buy underwear?

Not every time, but it's worth doing whenever you try a brand you haven't bought from before, or if it's been a while since you last checked. Once you know your numbers, you can reuse them across most brands — just check that brand's own chart, since it may define waist or fit points slightly differently.