Your waist trainer size comes from your natural waist measurement, taken right above your belly button. Match that number to the chart for the trainer you want, because each line has its own chart. If you land between two sizes, go up one for your first trainer and down one if you've worn a trainer before. Then pick your torso length (8", 10" or 12") separately.
That's the whole method. The rest of this post walks through each step, the signs a size is wrong, and what to do if it doesn't fit. If you'd rather skip ahead, the Find My Fit quiz asks for your waist and torso and picks the trainer, length and size for you.
How waist trainer sizing works
Most clothes are sized by one number. A waist trainer needs two. Size (XS, M, 2XL and so on) sets how far around it goes, and it comes from your waist. Torso length sets how tall it is, and it comes from the space between your ribs and your hips. Get the size right and the length wrong, and the trainer can still dig in or roll.
Our trainers come in sizes from 3XS to 3XL. The exact range differs a little by trainer, so check the size list on the product page you're looking at.
Step 1: measure your waist
The full walkthrough is in how to measure for a waist trainer. The short version:
- Use a soft tape measure, over bare skin or a thin top.
- Find your natural waist, right above your belly button.
- Stand relaxed and breathe out normally. Don't suck in. Sucking in gives you a number that's smaller than the trainer will actually sit on.
- Keep the tape level all the way around and snug, not tight. Read the number in inches.
Step 2: find your torso length
Sit up straight and measure from the bottom of your ribs to the top of your hip bone. Under 8.5 inches, choose the 8" Short. From 8.5 to 10.5 inches, the 10" Medium. Over 10.5 inches, the 12" Long. Most women wear the 10". Our torso length guide shows each step and what to do if you're right on a line.
Step 3: read your trainer's own chart
Here's where a lot of people go wrong. A medium in one trainer is not always a medium in another. Our 8" and 10" latex trainers share one chart, the 12" trainers use a different one, and the Luxx Hourglass, the Invisible Zip & Clip and the men's trainers each have their own. Always size from the chart for the exact trainer and length you're buying.
You'll find every chart in one place in our waist trainer size chart guide. The Invisible Zip & Clip runs small, so order one size up from its chart.
Active Sculpt Waist TrainerFlexible latex with three rows of hooks, in 8", 10" and 12". A good first trainer, so the size-up rule for first-timers usually applies here.From $79Shop 
Daily Sculpt Waist TrainerOur firmest everyday latex. If you've worn a trainer before and want a snug hold, this is where the size-down rule comes in.From $79Shop Between two sizes?
If your waist sits right on the line between two sizes, think about your experience, not your dress size.
- First waist trainer: go up one size. A new trainer feels firm, and the extra room makes the first weeks easier while your body gets used to it.
- Worn one before: go down one size for a snugger hold. You already know how the compression feels.
Fit also varies from body to body, so two people with the same waist can feel differently in the same size. Our customers show that. One wrote: "I ordered a medium but it was too big. Definitely exchanging for a small." Another said: "True to size. I’m 5’10” 180 got a size medium." Neither is a rule. They're a reminder to trust your tape measure and the chart over a guess. Still deciding which trainer to get? Start with how to choose a waist trainer.
“Comfortable and fits great. It does not move, but found that I could go down a size so I ordered a Small the next day.”
Signs it's too small
- You can't close the loosest row of hooks, even after a few tries and a little patience.
- It pinches, causes pain, or makes it hard to take a full breath.
- The edges bulge or the boning pushes into your ribs.
- Your skin goes numb or tingly, or gets red and irritated.
If you feel pain, numbness, shortness of breath or skin irritation, take it off. That's true for any size. More on what the right feel is in how tight a waist trainer should be.
Signs it's too big
- It closes easily on the tightest row and you feel little or no hold.
- It slides down, twists or shifts when you move.
- There's a gap at the front or back.
A trainer that rolls at the top or bottom is a different problem. That's usually length, not size. See why your waist trainer rolls up.
What if it doesn't fit?
Try it on as soon as it arrives, over a thin top, with the tags still attached. If the size is wrong, request an exchange within 24 hours of delivery and send it back within 7 days. Your first exchange is free. Trainers are undergarments, so they need to come back unworn and unwashed with tags attached. All sales are final otherwise. The full terms are on our exchanges and returns page.
“Amazing waist trainer and an amazing customer service! I ordered the wrong size and length originally and they made the exchange process so easy! Would recommend this company and its products to anyone I know!”
Should I order my dress size?
No. Dress sizes vary too much between brands. Measure your natural waist and use the chart for the trainer you want. Your trainer size and your dress size often don't match.
Do waist trainers run small?
It depends on the trainer. Most of ours fit to their chart. The Invisible Zip & Clip runs small, so order one size up. A new latex trainer also feels firmer at first than it will after a few wears.
Is it normal for a new trainer to be hard to hook?
Yes. The first rows take some effort, and a new trainer loosens a little as it breaks in. It should feel firm, not painful. If you can't close the loosest row at all, or it hurts, it's likely too small.
Can I exchange if it doesn't fit?
Yes. Request it within 24 hours of delivery and send the trainer back unworn within 7 days. Your first exchange is free. Details are on exchanges and returns.
