Taking accurate body measurements is the single most reliable way to buy clothes online that actually fit, because a body measurement doesn't change from brand to brand the way a size label does. This guide covers the tools you need and step-by-step instructions for every major measurement, including bust, waist, hips, inseam, and bra size.
Getting set up correctly
Use a soft, flexible measuring tape — the kind used for sewing — rather than a rigid carpenter's tape. If you don't have one on hand, a piece of string measured afterward against a rigid ruler works just as well. Measure over the undergarments you would normally wear with the type of clothing you're shopping for, since a padded bra or thick socks can shift a measurement by half an inch or more. Standing naturally, without pulling in your stomach or over-tightening the tape, is essential; the tape should be snug against the skin but not compressing it, and you should be able to slide a finger underneath it. Where possible, have someone else take the measurement for you, since it's difficult to keep a tape level and horizontal around your own back.
Core body measurements, step by step
Chest and bust
For men, wrap the tape around the fullest part of the chest, passing just under the armpits and across the shoulder blades, keeping it horizontal. For women, measure around the fullest part of the bust while wearing a non-padded bra; this is the number used for tops, dresses, and jackets. Breathe normally rather than expanding your chest for the measurement.
Looking for a specific brand?
Fit varies far more between brands than between size systems.
Browse 30+ brand size chartsWaist
Your natural waist is the narrowest part of your torso, typically one to two inches above the belly button — not where your jeans usually sit, which is your hip line. Measure at the end of a normal exhale, and repeat two to three times to confirm consistency. The most common mistakes are measuring over thick clothing, pulling the tape too tight, or accidentally measuring at the hip instead.
Hips
Stand with your feet together and measure around the widest part of your hips and buttocks, keeping the tape parallel to the floor.
Inseam
The easiest method is to lay a well-fitting pair of pants flat and measure from the crotch seam straight down to the bottom hem. If measuring on your body, stand against a wall in flat shoes and measure from the inner thigh, where the crotch of your pants sits, straight down to the floor. Standard inseam lengths run short (28–30 in), regular (32 in), long (34 in), and extra-long (36 in); if you're between two lengths, size up, since a longer inseam can be hemmed but a short one can't be lengthened.
Measurement reference table
| Measurement | Where to measure | Common mistake |
|---|---|---|
| Chest / bust | Fullest point, tape horizontal under arms | Pulling the tape too tight |
| Waist | Natural waistline, 1–2 in above navel | Measuring at the hip line instead |
| Hips | Widest point of hips and seat | Feet apart, skewing the tape angle |
| Inseam | Crotch seam to hem on flat pants | Measuring outseam instead of inseam |
| Shoulder width | Seam to seam across the back | Measuring while slouching |
Finding your bra size at home
Bra sizing combines a band measurement and a cup measurement, and both are easy to take yourself with a soft tape. First, measure your band by wrapping the tape snugly around your ribcage, directly under your bust, keeping it level and parallel to the floor; round to the nearest whole number, and add 4 if the result is odd or round up to the next even number, which is the traditional method many US brands still reference (some newer "true fit" calculators skip this add-on step, so check the specific brand's instructions). Next, measure your bust size around the fullest part of your chest while wearing an unpadded bra. The difference between your bust measurement and your band measurement determines your cup size.
| Bust minus band | Cup size |
|---|---|
| Less than 1 in | AA |
| 1 in | A |
| 2 in | B |
| 3 in | C |
| 4 in | D |
| 5 in | DD / E |
| 6 in | DDD / F |
If your calculated size feels off once you try a bra on, adjust the band first — most fit problems come from a band that's too loose, which pushes the weight of the bust entirely onto the shoulder straps.
Putting your measurements to work
- Write your measurements down and re-check them every six to twelve months, since bodies change gradually over time.
- Compare your numbers against the specific item's chart rather than a generic "size guide," since even one brand's jeans and dresses can use different base charts.
- Use our size converter to translate your measurements into a specific brand and size instantly.
- When you're between two sizes, check the brand's own fit notes; some recommend sizing up for structured fabrics and sizing down for four-way stretch.
For more on how these measurements translate into a specific numeric or letter size, see our guide on letter sizes to numbers.