Multi-Brand • 14 Brands • 3 Input Methods • 2026
Bralette Size
Converter
The only tool that shows your size across 14 major brands simultaneously — convert from your bra size, your measurements, or your current brand.
Quick Answer: Bralette sizing varies wildly between brands — an M at Aerie is not the same as an M at Skims or a S/M at Lively. Our Bralette Size Converter lets you enter your regular bra size, your measurements, or your size in one brand, and instantly shows your size across 14 major brands simultaneously — including a fit confidence meter, international sizing, and style recommendations for your cup equivalent.
Here’s something that happens to almost everyone who shops for bralettes: you find a style you love, check the size chart, pick what should be your size, and when it arrives it’s either pulling across the back or swimming on your chest. You return it. You size up. That one doesn’t fit right either. Eventually you give up and go back to the brand you already know.
It’s frustrating — and it’s almost entirely caused by one thing: bralette brands don’t share a sizing standard. Not even close.
Why Bralette Sizing Is So Inconsistent
Traditional bras use a two-part sizing system (band number + cup letter) that at least provides a structured framework. Bralettes skipped that entirely. Most brands just use XS through XXL or XS through 3X — which sounds simpler, but it means every brand is drawing their own lines between those letters based on their own fit models, fabrics, and design philosophy.
Take a concrete example. At the time of writing:
Aerie’s Medium fits an underbust of roughly 30–33.5 inches. Skims’ Medium fits 30–33.5 inches too — but their fabric is considerably more compressive, so the same measurement feels tighter. Meanwhile Lively doesn’t even have a standalone M — their sizing comes in XS/S and M/L because their stretch fabric covers two standard sizes at once. And Pepper, which is designed specifically for AA–B cups, cuts their sizes narrower through the cup regardless of underbust.
None of this is on the size chart. You’d only know it from buying and returning across all four brands — or from a converter that’s actually mapped the differences.
That’s exactly what this tool does.
Editor-Approved Bralettes by Cup Size
These are the most consistently well-fitting styles across 14 brands — selected based on structure, stretch behavior, and long-term wear comfort.
| Product | Best For | Support | Comfort | Daily Wear |
|---|---|---|---|---|
| Calvin Klein | AA–B | Light | ★★★★★ | Excellent |
| True & Co Lift | C–DD | Medium-High | ★★★★☆ | Best Overall |
| Aerie Longline | B–C | Medium | ★★★★☆ | Great |
| Wacoal Wire-Free | DD+ | High | ★★★★☆ | Structured Support |
What the Bralette Size Converter Does
The converter gives you three ways to get your results, because people come to bralette sizing from three different starting points.
Method 1 — You know your regular bra size. Enter your band and cup (say, 34B or 36D) and the tool calculates your equivalent underbust measurement, applies a cup modifier, and maps that across every brand’s size chart. This is the most common starting point and works well for most people.
Method 2 — You have your measurements. Enter your underbust in inches or centimetres (bust is optional but helps refine your style recommendations). This is the most accurate method — measurements don’t lie the way labels do.
Method 3 — You know your size in one brand. This is the feature no other tool offers. Select the brand you already shop, enter your size in that brand, and the converter uses that brand’s known underbust range to map your size across all 13 others. Shopping Savage X Fenty for the first time but only know you’re an L at Calvin Klein? Done.
Whatever method you use, your results include the same four things: your universal size with a confidence meter, your international sizing (US, UK, EU, AU, FR), your size across all 14 brands with individual notes on each, and a style guide based on your cup equivalent.
The 14-Brand Grid: Why It’s the Most Useful Part
The brand grid is the centrepiece of the tool — and the reason most people bookmark it.
Every result screen shows all 14 brands at once: Aerie, VS PINK, Free People, Lively, Pepper, True & Co, Savage X Fenty, Calvin Klein, Skims, Natori, Hanky Panky, b.tempt’d by Wacoal, ThirdLove, and Parade. Each brand card shows your confirmed size in that brand, any adjacent sizes worth trying, and a brief note about how that brand tends to run.
The colour coding matters. Pink highlighted cards are your confirmed size — the brand’s range cleanly covers your measurement. Gold highlighted cards mean you’re sitting right on the borderline of two sizes, and the tool tells you to try both. This borderline identification is genuinely useful: a lot of sizing frustration comes from being between sizes at a brand that doesn’t have a half-size option, and knowing that upfront saves a return.
The individual brand notes are practical rather than marketing-speak. Skims’ note says “Body-con sizing. Size up for comfort fit.” Lively’s explains the XS/S and M/L dual-size format. Pepper’s flags that it’s specifically designed for AA–B cups. These are the things you’d learn from reading 40 Reddit threads — condensed into one line per brand.
The Fit Confidence Meter: A Feature That Didn’t Exist Before
One thing that’s always been missing from size converters is any indication of how well the result fits, not just what the result is.
If your underbust is 30.2 inches and a brand’s Medium starts at 30 inches, you’re technically in Medium — but you’re right at the bottom edge of it, which means that bra is likely to feel loose within a few weeks of washing and wearing. The confidence meter shows this. It calculates where your measurement sits within the size range (centered vs. edge) and gives you a percentage confidence score along with a plain-English label: “Perfect fit zone,” “Good fit zone,” “Borderline — try both sizes,” or “Edge of size range.”
When you’re borderline, the tool also tells you specifically which adjacent size to try — not just “you might want to size up” but “you’re at the top edge of S, try M if your current S feels snug after a few washes.”
The Style Guide: Not All Bralettes Work for Every Cup Size
This is where a lot of bralette disappointment comes from that has nothing to do with brand-to-brand sizing — it’s about choosing the wrong style for your cup size.
The converter includes a style guide based on your cup equivalent. Here’s the honest version of what it says:
For AA–A cups: Triangle bralettes and unlined lace styles are genuinely your best option — the fabric drapes perfectly, nothing gapes, and you don’t need structure you won’t use. Heavy padding usually looks disproportionate and is unnecessary.
For B cups: You have the widest range of options. Lightly lined cups (thin foam lining, not padding) give you the most versatile everyday option. Triangle bralettes work for light activity but may not feel secure enough for all-day wear.
For C cups: Structure starts to matter. Look for bralettes with moulded or shaped cups rather than fully unlined ones. Longline styles are worth trying — the wider band distributes support better and prevents riding up.
For D–DD cups: This is where the category starts to show its limits. A longline bralette or a structured wire-free style (True & Co and ThirdLove both make these) is your best bet for real daily wear. Standard triangle bralettes are fine for the sofa but probably not for a full work day.
For DD+ cups: The tool is direct about this: most bralettes aren’t going to give you adequate support, and a well-fitted wire-free bra will serve you significantly better. If you want the bralette aesthetic, longline styles are the best available option — but manage your expectations.
International Sizing: The Strip Nobody Else Includes
If you shop from international retailers — ASOS, Zalando, brands that ship from Europe or Australia — the international sizing strip at the top of your results shows your equivalent size across five markets simultaneously. US, UK, EU, AU, and FR.
Bralette sizing internationally follows the same underbust-based conversion as traditional bra sizing for band measurements, but the letter conventions differ. An EU 75 is a US 34. An AU 12 is a US 10. The strip takes your universal size and cross-references it across all five systems so you’re not doing mental arithmetic with a size chart in a language you don’t read.
Frequently Asked Questions About Bralette Sizing
What size bralette should I get if I wear a 34B bra?
A 34B typically converts to a Small in most bralette brands. Your underbust of approximately 30.5 inches puts you comfortably in the small range at Aerie, Calvin Klein, b.tempt’d, and ThirdLove. At Lively, you’d be in XS/S. At Skims, which runs slightly compressive, S is still your size. Use the converter to see your confirmed size at all 14 brands at once.
What size bralette should I get if I wear a 36C bra?
A 36C typically converts to a Medium in most bralette brands. The 36 band puts your underbust around 32–33 inches, and the C cup modifier shifts you slightly toward the upper end of medium. At brands that run small (VS PINK), you may find a Large more comfortable. The converter shows you all options with confidence ratings.
Why does my bralette size feel different between brands?
Because bralette sizes are not standardized. Each brand sets its own underbust ranges for XS–XXL based on their own fit models and target demographic. Brands with more compressive fabrics (Skims, for example) effectively run small because the fabric does less stretching. Brands with stretchy jersey (Parade, Hanky Panky) often cover two standard sizes in one label. The only way to know for sure is to map your measurement against each brand’s individual chart — which is exactly what this tool does.
How do I measure my underbust for a bralette?
Wrap a soft measuring tape snugly around your ribcage, directly underneath your breasts. The tape should be horizontal and parallel to the floor. Breathe out normally and read the measurement while exhaling — you want the natural circumference, not your maximum exhale or a pulled-tight measurement. This is your underbust measurement. For bralettes, this is more useful than your bra band size because bralette fabrics stretch in ways that band-based sizing doesn’t account for.
Do bralettes come in cup sizes?
Most bralettes don’t use cup-letter sizing — they use generic S/M/L/XL sizing that accounts loosely for both underbust and cup volume together. A few brands (True & Co, ThirdLove, and some Wacoal styles) offer cup-inclusive bralettes with more precise sizing. If you have a larger cup size (D+), cup-inclusive styles are worth seeking out since generic sizing often underserves larger cups.
What’s the best bralette brand for larger cup sizes?
For D–DD cups, True & Co and ThirdLove make the most genuinely supportive bralette-adjacent styles. For DD+ cups, the honest answer is that most bralettes won’t offer sufficient support, and a well-fitted wire-free bra from a specialist brand is a better investment. If the bralette look matters to you, longline styles from Savage X Fenty or Aerie’s longline range give more band coverage and better support distribution.
What bralette size is equivalent to XL in regular clothes?
XL clothing and XL bralette sizing don’t always correspond. Bralette XL is based on your underbust measurement (typically 36–40 inches depending on brand), not your overall clothing size. You can be an XL in tops but a Medium in bralettes if you carry your size more in your hips or shoulders. Use your underbust measurement, not your clothing size, as your starting point.
How is Skims bralette sizing different from other brands?
Skims sizes run slightly small due to the brand’s body-con, compressive aesthetic. If you’re between sizes at another brand, sizing up at Skims is usually the right call. Their XS starts at approximately 22 inches underbust and 4X goes up to 52 inches, making it one of the more genuinely inclusive size ranges available. The converter marks Skims cards with a note about this tendency.
What is the difference between XS/S sizing and standard XS or S?
Some brands (notably Lively and Hanky Panky) sell bralettes in combined sizes like XS/S or M/L because their fabrics are stretchy enough to fit both sizes in a single garment. An XS/S at Lively covers the same underbust range as an XS and S separately at a brand like Aerie. The converter accounts for this and maps your measurement correctly — you won’t be shown a combined size if you clearly sit at one end of it.
A Note on How This Data Is Maintained
The brand size data in this converter is based on published sizing guidelines from each brand’s official size charts, cross-referenced with documented fit notes from specialist sizing communities. Bralette sizing does change — brands update their ranges, introduce new fits, and occasionally recut their size blocks between seasons.
We review and update the brand data periodically, but bralette sizing can shift between product lines within the same brand (a Lively T-shirt bralette may fit differently from their longline style in the same size). The converter gives you the most accurate starting point available — but always check the individual product’s size chart before purchasing, particularly for newer releases or seasonal collections.
The disclaimer inside the tool says the same thing. We’d rather tell you that upfront than have you return three packages thinking the tool was wrong.
Use the Converter
The Bralette Size Converter is embedded above this article. Three input methods, 14 brands, confidence ratings, style guide, and international sizing — all in one place, all in under a minute.
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