How to Measure Bra Size

The solution: Measure yourself! Here’s how.

Underbust band: This is the measurement of your torso, well, under the bust. It comes in numbers: 32, 34, 36, 38, 40, 42, 44, and beyond! 32 is smaller and 44 is larger.

Cup: This is the measurement of the volume of the bust. It comes in letters: A, B, C, D, DD, and beyond! A is smaller and DD is typically larger. The cup size represents a difference in inches between the band and bust measurements – one inch difference = A cup, two inches = B cup, and so on!

If your bra size is 38B… The number 38 is your underbust measurement. The letter B is your cup size. 

The solution: What is a sister size for bras and how does it work?

Every bra size comes with 2 sister sizes. For example, if you wear a 34B, you can also wear a 36A or a 32C. “How can that be?” you may be wondering. We’ll explain!

The bust volume is a calculation including the band size and the cup size. A 34B and 36A, for example, have the same cup size because the volume of the cups is the same.

Knowing your sister sizes is helpful because it gives you more options. If you’re shopping for bras from a company that doesn’t carry your exact bra size, you may be able to find your sister size instead!

Although the cup volume should be the same between sister sizes, the band size will be a little different. If you buy a 36A instead of a 34B, you may have to wear the bra with the second row of hooks fastened instead of the outermost ones; otherwise, it may fit too loose. If you’re trying on a 32C instead of a 34B, your band will probably be too tight, so you may want to try bra extenders.

The solution: You may be wearing too small of a bra and not even know it. It’s pretty common! But if you’re wearing a bra with too small of a band, a band that isn’t wide enough, or a band that’s not stretchy enough, you may find yourself dealing with “back rolls” as a result. When this happens, you have two options: measure yourself again and find a bra that will fit, or wear a bra extender to extend the band of the bra you already have.

Wearing a bra that’s too small isn’t necessarily dangerous to your health, but it may lead you to develop back, shoulder, breast, and ribcage pain. You may also notice skin abrasions and chafing from the bra rubbing against your skin. Not only that, but if you wear a bra that’s too small for too long, it can create indentations on your body where you didn’t have any before.

The Solution: Because a lot of people are wearing the wrong bra size, statistically, this is relatively common. If you’re wearing a bra with too-small cups, your breasts will spill out of the top, giving you the “quad boob” look. You can even see it through your shirt.

To resolve this, try wearing a bra with cups the next size up. For example, if a 34B gives you quad boob, maybe a 34C will work better! You can also try cups with different levels of coverage. At Leonisa, we carry bras in many different silhouettes, from demi cup to full coverage.

The solution: If your underwire is riding up, you’re either not wearing the bra size or not putting your bra on correctly.

If you’re wearing a bra with too small of a cup size, it’s not going to fit well and that can lead the underwire to ride up, sitting over your breasts instead of underneath. Not only is this uncomfortable, it’s also not giving you the support you need.

If you’re certain the bra is the right size, but it’s still not sitting right, try sliding your hand into the cup, grab that boob, and move it up over the underwire and towards the center of your chest. When you let go, it should be positioned correctly, resting on the underwire for support.

The solution: This happens most often to small-chested folks, who may have a harder time filling out bra cups, but it can happen to anyone.

One option is to switch to bralettes or bras specially designed for smaller busts. However, you can also try demi cup bras or padded bras, also known as push-up bras. Not only does the padding give your chest a lift, it also serves to fill out the cups a little more, so they should fit better.

If you have a fuller bust, the issue may be that you’re wearing the wrong size bra with cups that are just too big. If that’s the case for you, we have bras for an average bust and bras for a full bust so that you can find a bra that fits and supports you!

If you chose a bra size that fits perfectly in the back, but too big in the cups, consider switching to a bra that fits perfectly in the cups instead. If it’s too tight in the back, you can always wear it with bra extenders to create extra space in the back for that perfect fit!

The solution: Does the back of your bra sit like this? That’s a very common problem to run into and it usually happens for 2 reasons. One reason is that you’re wearing a bra with too-tight straps. That’s not just an issue of aesthetics – it’s also painful!

The second reason is that you’re wearing a bra with too big of a band. If the band is too big, it won’t sit right in the back.

So, how should the back of your bra fit? Your bra band should sit straight across in the back and shouldn’t ever ride up. If it’s riding up and creating an arch, it doesn’t fit right.

The solution: There’s nothing more uncomfortable than ill-fitting straps. If they’re too tight, for example, they’ll dig into your shoulders. When you take off your bra, does it leave you with red marks and indents? That’s not supposed to happen!

The opposite also happens: sometimes your straps are too loose, which is also uncomfortable because you have to keep pulling them up throughout the day. Not only that, but wearing a bra with too-loose straps makes everything look droopy.

Your bra supports your bust in 2 ways. The majority of the support should come from your underbust band, but the straps also play a role in holding the bra up. That’s why it’s important to find a perfect fit in both! If you need a little extra support, try switching to a bra with wider straps.

Most of our bras have adjustable straps. If they’re too tight, you can loosen them up for a perfect fit. If they’re too loose, you can tighten them up! But if you’ve adjusted the straps and they still don’t fit well, try removing them and replacing them with the straps from a bra you know fits. You can also buy straps separately and see if those will fit!