The first bras that were ever made were one-size-fits-all. And then came the sizing system, and it's no secret that only one group of girls get to call themselves the A-listers - that's right, it's us, the A-cup size girlies. If you're an A-lister and want to know more about your boob squad, you're in the right place. We've been working hard to make sure AA and A size girls get the best fit and choice of styles for years now. If you're new here and have no idea what we're on about, read on to learn lots of fun trivia and get measured up!

What It Means to be an A Cup Bra girl: Measuring Bra Cup Sizes

[The answer is - not a lot. You've just gotta be you, get yourself a measuring tape, and have a blast with the girl math.]

The way you know what bra size and measurements you are is by measuring your band size and bust size. This is super easy to do, and we've got you a step-by-step guide on how to measure your cup size to know if you're an A-cup girl, with our home measuring guide and and a reader on all things sizing for A girls.

Let's get right into how to tell what cup size you are.

Step 1: Get Your Band Size

Wrap a measuring tape around the chest, right below your breasts. It's the part where your bra's band sits snug and does the work supporting your breasts. Make sure the tape sits comfortably - not too tight, not too loose.

The reading you get from the tape is your band size in inches.

Step 2: Measuring Bust Size for a Bra

Next, wrap the tape in the same way over the fullest part of your breasts - so that the tape runs over your nipples. Make sure the tape isn't digging into your chest or too loose.

The reading you get from the tape is your band size in inches.

Step 3: How to Measure Breasts for Cup Size

Easy peasy! Your cup size is the volume of your breasts. It's the difference between the flat portion of your chest and the busty bit, a.k.a your boobs.

To get your cup size, all you've to do is subtract your band size from your bust size.

Bust Size - Band Size = Cup Size.

A cup bra size girl is a girl whose breast measurements are an inch greater than their band line measurements—making you "busty" by an inch of breast tissue.

So, if your band size is 32in and your bust size is 33in, you're an A-cup bra-size girl. You're also an A-cup bra-size girl if your band size is 33.5in and your bust size is 34.7in. That's because your cup size is 1.2 inches, and you can round off your size to the closest whole number.

Step 4: Online Bra Shopping with Bra Cup Size Examples

The fun bit is that you can go bra shopping with another girl from the A-cup bra-size girl squad and still end up with different bra sizes. How does that work? That's because your bra size is your band size and cup size put together. So, for instance, if your band size is 32 inches and your cup size is an A, that makes you a size 32A. Let's say your bestie is an A, too, but her band size is 34, then she's a 34A, and you'll need to look for different bras in the same cup size.

Can A girls and B girls be friends/sisters?

So, we know. Every girl squad has a girl code, and the question always is, can squads be friends with other squads. The answer is yes, especially when you're a bra girl - and here's why. In the world of bra girls, we want our sisters to be able to grow when their bodies grow.

Life's not always going to be the same. Your body's likely to change with changes in lifestyle, breastfeeding, hormonal changes, and other factors. It may or may not, but whatever happens, we embrace change fully. So chances are your best girls in the A cup bra size girl squad may grow or lose size and leave….and that's ok!

There's one other way A girls and B girls can be friends…by switching places. You read that right!

Bra sizes have sister sizes meaning that you can have more than one bra size. Your bra supports your breasts at the band, but your bra can sit very firm, just right, or looser at the band. So, for instance, if you're 34in at the band, you can go down an inch on your band size for a snugger fit. But when you do that, you'll need to go up a cup size. This is because when the band size of a bra decreases, so does its cup volume. If a 34A girl goes bra shopping and decides that she needs a sports bra with a tighter fitting band line, she can buy a bra that's 32B. So, the band size goes down, and the cup size reading goes up.

This means that an A cup bra size girl can be a B-cup bra size girl depending on the bra style and the correct bra fit for that style.

To know more about sister sizing, read our deep dive on the subject here.

Bra Size and Measurements: What do A Cup Bra size boobs look like?

Even within the A cup bra size boob squad, we're each unique and different. No two boobs are alike. They look different based on how the volume of your breast tissue gets distributed through your breasts and by shape. A cup boobs measure between 0.9 inches to 1.7 inches. Whatever your boobs look like, one thing we know is that - the phrase "small is beautiful" was invented to describe the A cup bra size girl squad.

Best Bras for A cup bra size girls

Some styles just work effortlessly on A cup bra size girls. Like the comfy cami bra top you can flaunt wherever you go with A cup bra size petite privilege (pro-tip: the longline cami bra adds flair to special occasions). A well-designed stretch bra that contours and shapes like a corset puts A cup bra size girls right on top of their fashion game. And, always remember – athleisure was tailor-made for A-cup bra-size girls like us, so we decided to add a touch of drama with these lace halter bralettes . As Acup bra size girlies, more drama is what we want – bring on the straps, lace, and pretty patterns – works wonders for our overall look!