Clothing sizes vary from brand to brand because there is no universal sizing standard. A "medium" is not a measurement. It is a label each brand defines for itself, which is why the same body can be a small in one shop, a medium in another, and a large in a third, all in the same week. This is normal, it is not a comment on your body, and once you understand why it happens, size charts stop being confusing and start being useful.
Why am I a different size in every brand?
Four things are going on at once.
There is no enforced standard. The United States once had official government size guidelines, but manufacturers stopped using them as the standard in 1983. Since then, every brand builds its own size chart, and most do not follow the voluntary industry standards that still exist on paper.
Vanity sizing shifts the labels. Many brands deliberately label garments smaller than their measurements suggest, on the theory that you will feel better, and buy more, wearing a smaller number. The drift over time is dramatic: a dress with a 32 inch bust was a size 14 in 1937, a size 8 by 1967, and a size 0 by 2011. Research has also found that more expensive brands often cut smaller than cheaper brands at the same labeled size. The number on the tag is marketing as much as measurement.
Every brand fits a different body. Brands develop their patterns on a base body, called a fit block, usually tested on one fit model, then scale that shape up and down to make the other sizes. A brand whose fit model has a small waist relative to her hips will produce a different garment than a brand whose fit model is straighter through the middle, even if both call it a size 8. Brands also cut for their target market: a label aimed at teenagers cuts differently than one aimed at athletes.
International systems do not line up. A US 6, a UK 10, and an EU 38 are roughly the same body, but conversions between systems are approximate, and many polewear brands are based in Australia, the UK, or Europe. If you order from a brand abroad, assume nothing and check the chart.
What does "fit" mean when the fabric stretches?
Polewear is cut with negative ease, which means the finished garment measures smaller than your body. A pair of stretch shorts with a 24 inch waistband might be intended for a 26 or 28 inch waist. The fabric stretches to reach your measurements and the tension is what holds the garment against your skin.
This flips the usual logic of fit. In a woven garment, like jeans, the garment must be bigger than you or it will not close. In stretchwear, the garment is supposed to be smaller than you. So when a size chart says a small fits a 26 to 28 inch waist, it does not mean the shorts measure 26 to 28 inches flat. It means the brand designed that size to stretch comfortably across that range. Typical activewear carries around 1 to 3 inches of negative ease, and how much a given garment can handle depends on the fabric's stretch, which is one more reason two brands' charts disagree.
How do I measure myself?
You need a soft tape measure, or a piece of string and a ruler. Wear thin clothing or underwear, stand relaxed, and keep the tape snug but not compressing.
- Waist. Measure around your natural waist, the narrowest point of your torso, usually around or just above the belly button. Do not suck in. Breathe out normally and measure.
- Hip. Measure around the fullest part of your hips and butt, typically 7 to 8 inches below your waist. Keep the tape level all the way around, including in back. A mirror helps.
- Rise. Rise is how high a waistband sits, measured from the crotch seam up to the top of the waistband. High rise generally means about 9 inches or more and sits at or above the navel. Mid rise sits around the navel, low rise below it. For shorts, rise decides whether the waistband stays anchored when you invert, so it is worth noticing which rise you prefer.
Write your numbers down. They change slowly, and having them saved makes every future order faster.
How do I read a brand's size chart?
Find the chart for the specific garment, not just the brand, since bottoms and tops are often charted separately. Then match your measured waist and hip to the chart's ranges and let the chart overrule your usual letter size completely. For bottoms, hip is usually the measurement that matters most; for high waisted styles, weigh the waist number more heavily. If a brand lists garment measurements instead of body measurements, remember negative ease: the garment should measure at or below your body numbers, not above.
What if I fall between sizes?
Gym advice usually says size up for comfort. Pole flips that, because in pole two things matter more than they do in the gym: coverage and staying put. Shorts that shift, gape, or ride up mid spin are a real problem, and loose fabric between your skin and the pole costs you grip. So the general rule for polewear is: if your waist and hip point to different sizes, or you sit between two, favor the size that matches your measurements snugly rather than sizing up for roominess. The fabric is built to stretch; a snug fit that stays anchored through an invert will serve you better than a relaxed one. The exception is compression discomfort: if a waistband digs in painfully, that size is simply wrong for you, whatever the chart says.
Measure yourself, trust the chart over the label, and expect your size to change from brand to brand. It is the charts that are inconsistent, not you.
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