Why Is Swimwear So Small? (And Why You Always Have to Size Up)

I thought my body was the problem.

Before I started my brand - Tranquila Swimwear, I was constantly ordering bikinis that were way too small on me. 

I was so tired of ordering my usual size, trying it on, and immediately thinking there’s no way this is right.

And then doing the whole guessing game - should I size up once? Twice? Is it supposed to fit like this? Is something wrong with my body???

So when I designed my Tranquila pieces, I made it a priority that you wouldn’t have to size up two times just to feel comfortable. Swimwear should fit your body - not fight with your body.

But the more I got into this industry, the more I realized this wasn’t just a random issue. There are actual reasons why so much swimwear runs small and here are why.

1. Swimwear Is Designed On One Body Type (The Skinny Type)

A lot of bikinis are designed and fitted on very specific body types, and then graded up or down for other sizes. The problem is, bodies don’t scale like that in real life. The sizing differences don't take into account the differences and curves that come with increased sizing. So what ends up happening is a “standard” that doesn’t really fit most people properly.

When I started Tranquila Swimwear, I saw firsthand how important it is to get different fit models for each size, to ensure a proper fit.

2. Inconsistent Sizing Across Brands

A medium in one brand can feel like a small (or even an extra small) in another. There’s no real consistency, which is why so many of us are used to automatically sizing up when we shop for swimwear, mainly for the #1 reason why swimwear is so tiny in the first place - because it's designed on one body type.

THE REAL ISSUE THAT NO ONE TALKS ABOUT

Somewhere along the way, it became normal to feel like your body is the issue.

Like if something doesn’t fit, it must be you.
Like you need to change sizes, adjust, or just get used to it.

But honestly, that’s backwards.

Swimwear should feel secure, comfortable, and flattering. You should not have to constantly adjust it or second-guess your size. You also shouldn’t have to mentally prepare yourself just to try on a bikini.

So, what to do? Look for these when shopping for a bikini:

1. True to size fit: look for sections on the product page that talk about fit.

2. Pictures: Look closely at the model pictures (even better: try to find a model that has YOUR body shape) Does the bikini fit how it should? Is the bikini covering everything it needs to?

3. Fabric: Pay attention to the fabric. High-quality materials offer better support and have the right amount of stretch to comfortably mold to your body.

4. Coverage: Make sure the coverage is not impractically small. If the model is a size Small and it is not covering as much as it should, then chances are the bikini runs small.

This is me ordering a bikini from another brand to see how it fits. The left side is a medium in top & bottom (my usual size). The right is our Faye bikini in a size Medium. Isn't the difference crazy?! I was completely spilling out of the top on the left, there is no way I would ever wear it out. And the bottoms.... I don't think I need to explain myself there. You can bet I had body dysmorphia the second I put that bikini on.

It's not you. It's the swimwear sizing.

It's why I built Tranquila to fit TRUE TO SIZE.

Tranquila Swimwear was created with this exact frustration in mind.

I didn’t want pieces that only looked good for photos. I wanted something you could actually wear, feel good in, and not have to overthink. Something that fits the way it’s supposed to, without the whole sizing-up guessing game.

Because once something fits properly, everything changes.
You’re not adjusting it every five minutes.
You’re not wondering if you should’ve picked a different size.
You just… wear it and enjoy your beach days.

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