How To Measure Swimsuit Size: Find Your Perfect Fit
Image Credit:Openai
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Arm yourself with your trusty measuring tape and discover how to measure swimsuit size—from one-pieces to bikinis—like a pro tailor.
Dresses, jeans, shoes, bras—you have to learn a lot of unique measuring systems to find clothing that hugs your body just right.
The same goes for swimsuits.
While each swimwear brand follows its own sizing guidelines, you can adopt a few key tricks to ensure your suit fits exactly the way you want it to. Read on to learn how to measure yourself, decipher a size chart, and find your perfect swimwear fit with confidence and ease.
All About Size Charts
Here’s the thing about swimwear brands—they all have their own sizing standards.
Typically, swimsuits are sized by either:
Alpha sizing (small, medium, large, extra large, etc.) or
Dress sizing (4, 6, 8, 10, 12, 14, 16 etc.)
While these systems create simplicity on paper, they can cause some issues if you don’t already know your size, or if you’re shopping a unique style (which swimsuits often are). And sometimes, a medium suit from one brand can feel more like a small from another—and on and on.
Some brands try to alleviate size discrepancies in the product descriptions; for example, they’ll say a suit is a “snug fit,” “loose fit,” or “true to size.” However, the most accurate way to predict how a suit will fit you is by looking at the size chart.
Size charts break down a piece’s sizing progression according to key body measurements: the bust, waist, and hips (usually). Of course, before you can apply a size chart to yourself, you need to know your measurements.
But don’t worry—I’ve got guides for that, too!
How to Measure One-Piece Swimsuit Size
Have your measuring tape at the ready? Good. Let’s begin!
When measuring yourself to find your swimsuit size, you’ll want to put on a different suit—your birthday suit. This ensures you take the most precise measurements possible.
Most swimwear brands base their one-piece sizing on bust, waist, and hips circumference. Here’s how to measure each:
Bust – Stand straight and wrap the measuring tape around the widest part of your bust, usually over the nipples.
Waist – Standing straight, wrap the tape around the smallest part of your torso, usually just above your belly button.
Hips – Standing straight, wrap the tape around the widest part of your hips, usually about 8-9 inches below the natural waist.
For accurate measurements, pull the measuring tape snug without pinching or digging, and make sure the tape stays even across your back.
With these measurements, you can read a suit’s size chart and determine your ideal fit!
To get a feel for one-piece sizing charts, let’s look at one from popular swimwear brand Beach Riot:
| Size | Bust (in) | Waist (in) | Hips (in) |
|---|---|---|---|
| XS | 31-32 | 23-25 | 34-36 |
| S | 33-34 | 25-27 | 36-38 |
| M | 34-36 | 27-29 | 38-40 |
| L | 36-38 | 29-31 | 40-42 |
| XL | 38-40 | 31-33 | 42-44 |
| XXL | 40-44 | 33-36 | 44-48 |
As you can see, the leftmost column shows the alpha sizes—A.K.A. the size you’ll select before checkout. In each size’s row, you’ll find a range of bust, waist, and hips measurements that fit within that size.
For example, if you have a 37-inch bust, 31-inch waist, and 41-inch hips, a large one-piece will likely fit you best. Each brand will break down their sizes slightly differently, so check their specific guide before choosing a size.
Image Credit:Beach Riot
Image Credit:Beach Riot
How to Find Your Bikini Size
Now that you know how to measure one-piece swimsuit sizes, let’s progress to level two: measuring bikini sizes.
Bikini Tops
Luckily, you now know how to measure bust-size for swimsuits. But for many bikini tops, you also need your under-bust measurement. To measure your under-bust, stand straight and wrap your measuring tape around the line just below your bust.
Let’s continue studying Beach Riot’s sizing guides, this time for bikini tops. They use the same sizing breakdown for bust and waist measurements, with the addition of the under-bust. Here’s how it shakes out:
| Size | Bust | Underbust | Waist |
|---|---|---|---|
| XS | 31-32 | 27-28 | 23-25 |
| S | 32-34 | 28-29 | 25-27 |
| M | 34-36 | 29-30.5 | 27-29 |
| L | 36-38 | 30.5-32.5 | 27-29 |
| XL | 38-40 | 32.5-35 | 31-33 |
| XXL | 40-44 | 35-37 | 33-36 |
Some brands also choose to size their swimsuit tops by bra size, especially for suits with underwire or larger cup sizes. While you likely know your bra size, it’s always a good idea to take updated measurements to ensure the right fit.
Here’s a handy bra size calculator from intimates icon and one of our affiliates, Victoria’s Secret.
Bikini Bottoms
Bikini bottoms size charts usually follow the same model for one-pieces—sans bust size. With your waist and hips measurements, you can find bottoms that fit as well as your favorite pair of undies.
Image Credit:Victoria Secret
Image Credit:Victoria Secret
Finding the Perfect Style for Your Body
Remember: Numbers are just numbers. There’s no waist or hip measurement you should be—only the one you are. When you find suits that fit you, the numbers and measurements simply fade away.
Take a page out of the body positivity book and choose styles that make you feel:
Comfortable
Beautiful
Uniquely you
By picking suits that align with your body’s natural lines and curves, you can feel more confident on the beach and in your skin.
Top Size-Inclusive Swimwear Brands
You can rock any swimsuit style as long as you grab the right size, and some swimwear brands are better at stocking inclusive sizes than others.
Here are the brands currently fueling body positivity with every size-inclusive one-piece and bikini:
Andie Swim – This beloved brand carries sizes from XXS to XXXL, with comprehensive size charts to boot.
Image Credit:Andie Swim
Image Credit:Andie Swim
Knix – This intimates and swimwear staple has an even wider size range, from XS to 4X, with plus sizes for women with larger cup sizes. They even have a built-in size calculator for their swim tops!
Image Credit:Knix
Image Credit:Knix
Alpine Butterfly – Spread your wings no matter your size by shopping from this size-inclusive powerhouse. They carry stunning suits in sizes XS up to 6X.
Image Credit:Alpine Butterfly
Image Credit:Alpine Butterfly
And there’s plenty more where that came from. So, even if a brand isn’t known for size-inclusivity, check their size offerings—you may be surprised to find they’re more inclusive than you thought!
Find the Fits that Truly Fit
Size is just one aspect to consider when finding your next swimwear showstopper. Discover iconic styles, dazzling colors, influencer-inspired looks, and more with MySwimLook.