The short version
- Measure, don't guess — dress and jean sizes are inconsistent between brands
- Three numbers matter: natural waist, fullest hip, and bust for bodysuits
- Between sizes? Size up — every time, for every style
- Waist and hips in different bands? Order to your hips
- Never size down for more control — it delivers less smoothing, not more
- Measure at the end of the day — your body fluctuates, and evening is the realistic number
Why dress size doesn't work
Dress sizing tells you almost nothing about your shapewear size. Clothing is cut with ease built in, so a size 12 in one brand fits a body that a size 8 fits in another — and neither number describes the measurements shapewear needs.
Shapewear works differently because it has to apply a specific compression across a specific area with no gaps. There's no ease and no margin. The garment is engineered against measurements, so measurements are what you have to give it.
This is the single most common sizing mistake, and it's the reason so many people conclude that shapewear "doesn't work for my body" when what actually happened was a size mismatch.
How to measure yourself: three numbers
Use a soft tape. Measure over bare skin or thin clothing. Keep the tape level and parallel to the floor, snug but not pulled tight — you should be able to slide one finger underneath. Stand naturally and don't hold your breath.
1. Natural waist
Your natural waist is the narrowest part of your torso, usually about an inch above your belly button and below your ribcage. If you can't find it, bend sideways at the hip — the crease that forms is your natural waist.
Wrap the tape around that point, keep it level all the way round, and record the number.
2. Fullest hip
Stand with your feet together. Measure around the fullest part of your hips and bottom, which typically sits 7–9 inches (about 20–23 cm) below your natural waist.
This is where most people go wrong. Measuring at the hip bone rather than at the fullest point of the seat underestimates your hip measurement — which is exactly how you end up with a garment that's too tight across the bottom and rolls at the leg.
3. Bust — for bodysuits and full-body shapers
Wrap the tape around the fullest part of your bust, keeping it level. Wear the bra you'd actually wear underneath, or none if the style is designed to replace it. For underbust styles you'll also want your underbust measurement, taken around the ribcage just below the breasts.
Two extras worth taking
- Torso length — for bodysuits, measure from the top of your shoulder down through the crotch and back up to the same shoulder. This determines whether a standard length will pull down at the shoulder or sag at the crotch.
- Thigh circumference — for shorts, measure the fullest part of your thigh, roughly 3 inches below the crotch.
Measure at the end of the day. Your body fluctuates by a small amount over the course of a day, and the evening number is closer to the conditions you'll actually be wearing the garment in. If you're buying for a specific event, measure wearing what you'll wear underneath it.
What to do when you're between sizes
Size up. This is not a hedge — for shapewear specifically, the larger size is the correct answer nearly every time.
The instinct runs the other way because "tighter equals more smoothing" feels intuitive. It isn't true. Compression works by distributing tension across a surface, and when the surface is too small for what it's containing, the tension concentrates at the edges instead of spreading. You get three problems at once:
- Bulging above the waistband, where the displaced tissue has nowhere else to go
- Rolling, because a band under concentrated edge tension folds over on itself
- Discomfort severe enough that most people take the garment off within an hour
A correctly sized shaper feels like a firm, even hug across the whole midsection. A too-small one feels like a fight.
When your waist and hips are in different bands
Order to your hips. This is the most common sizing scenario and the one most charts don't address.
Shapewear stretches upward through the waist far more comfortably than it stretches outward across the hip, so a garment sized to your hips will accommodate a smaller waist. Sized to your waist, it will be genuinely too tight across the seat — and that's the version that rolls, digs and gets returned.
If the gap between your waist and hip measurements is large, prioritise hips and consider a bodysuit over separates. A continuous garment handles a big waist-to-hip differential better than anything with a waistband, because there's no single point where the two measurements have to be reconciled.
Why sizing down backfires
It's worth being blunt about this, because it's the mistake that costs people the most.
Sizing down does not increase compression in any useful way. It compresses unevenly — hard where the fabric can reach, not at all where it's already at its limit — which is what produces visible rolls at the leg openings, armholes and waistband. The silhouette you end up with is less smooth than the correct size would have given you.
There's a durability cost too. A garment worn permanently at the limit of its stretch loses elastic recovery faster than one worn within its range. A size-too-small shaper wears out measurably sooner.
If you want more control, the answer is a firmer compression level or a longer-coverage style — not a smaller size.
Sizing for petite and tall frames
Torso length matters more than most charts acknowledge, and it's independent of your other measurements.
If you're petite (roughly 5'3" and under), a standard bodysuit may sit too long, so the crotch hangs low and the waistband lands above your natural waist. Look for a petite length, or choose shorts and briefs over full bodysuits — separates are far more forgiving of torso length.
If you're tall (roughly 5'9" and over), a standard bodysuit can pull down at the shoulders and ride up at the crotch. A tall length or a two-piece combination solves it.
For both: measure shoulder-to-crotch-to-shoulder before ordering a bodysuit. It's the measurement that decides whether a bodysuit is comfortable or unwearable, and almost nobody takes it.
Three checks when it arrives — before the tags come off
Do all three at home while the garment is still returnable.
- The finger test. Slide one finger flat under the waistband. If you can't, it's too small.
- The sit test. Put it on and sit down for a full minute. If it bunches, digs, rides up, or makes it hard to breathe comfortably, it's the wrong size — not something you'll get used to.
- The 20-minute mark test. Take it off after 20 minutes. Faint pink lines that fade in a couple of minutes are normal. Deep red indentations still visible after 20 minutes mean size up.
If any of the three fails, exchange it. Shapewear doesn't stretch to fit the way denim does — you can't break it in, and trying just wears the elastane out faster.
Find your Bloom size
Bloom runs XS to XXL and every style is $49.99. Our size guide has the full chart with waist, hip and bust ranges in both inches and centimetres — take your measurements first, then match them there.
If your numbers sit between two Bloom sizes, order the larger one. If your waist and hips fall in different bands, order to your hips. And if it's still not right when it arrives, exchanges are free within 30 days — the window exists precisely so you can do the three checks above at home.
Not sure where to start? The fit finder narrows it to one recommendation in three questions.
Source for the returns figure: Coresight Research (2025). Ready to find your size? The Bloom size guide covers XS–XXL in inches and centimetres.