What Does Bra Size Mean?

Numbers and letters, 30DD, 38F, 28AA, we see these sizes every time we look for a new bra, but now many of us really know what they mean? You might know that an A cup is smaller than a D cup. You might even know that the cup size AA is smaller than an A, despite DD being bigger than a D.

Confusing, right?

Don’t worry, we’re here to help clear some things up. Bra shopping becomes so much easier once you start to understand what’s going on!

What Does Bra Size Mean?

So, What Do Those Numbers Mean?

The numbers in the bra size refer to the band size. That is, the bit that goes around your ribs and holds everything in place. This is arguably the most important part of the bra despite the overwhelming focus we have on cup sizes. The band of the bra offers about 80% of the support given. That’s a big job. Band size is everything, without it there’d be no way of knowing your cup size!

Things to keep in mind:

Unfortunately, that number isn’t necessarily your measurement, some brands add a couple of extra inches to it for sizing but the lack of standardisation within the industry, however irritating for customers, is actually a great thing; it provides so much more variation so there’s definitely a bra out there that’s absolutely perfect for you, such as a comfortable triangle bra. After all, every body is unique, we can’t all fit into strict sizing codes.

What does cup size mean?

Wait, what?! What Does The Cup Size Mean Then?

The letters in the bra size are, of course, the cup size. The letter has nothing to do with the volume of your breasts which is why someone with 30DD’s and someone with 40DD’s will look completely different. In short, the cup size measures the difference between your band and your bust. Every inch your bust is larger than your rib cage, you go up a cup size, starting from A and going right up to whatever size is needed.

So, that person with the 30DD’s is going to have a lot smaller breasts than a person with 40DD’s (proving that cup size isn’t everything those boys on tinder think it is!). It’s also interesting to note that that person with 30DD’s will have the same sized boobs as someone wearing a 38A. This is called sister-sizing, but that’s a post for another time. 

What Does Bra Size Mean?

So, now you know what you’re looking at when you see bra sizes, shopping will be a lot less confusing. But, are you ready to start shopping? You’ll need to know your own size before you can start treating yourself. Not sure what yours is? Grab a tape measure and let us help with our size guide!


Check out a range of our bras and knickers we can perfectly size you for.

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We believe that the most important opinion of your body is your own. If the mainstream doesn’t think you’re fabulous, fuck em’.

Hayat - CEO & Founder, Neon Moon