How To Find your Bra Size

How To Find your Bra Size

There are few things in this world more uncomfortable than wearing an ill-fitting bra. It’s akin to the feeling of getting a bad sunburn, seeing an ex out in public, having a pebble stuck in your shoe, or doing cardio for the first time in 3 months. And not only are ill-fitting bras uncomfortable, every woman knows that they also shape your breasts in unflattering ways. Bands that are too tight press into your skin (hello back fat), bands that are too loose lack support, cups that are too small lead to pillowing and make it look like you have four boobs instead of just two, and cups that are too big make your shirt pucker outwards.

The tricky part is finding a bra fits you properly; a task that sounds relatively easy, yet in practice, can prove difficult. So, here at Miriam Baker, we’ve listed some simple tips to help you find your bra size and perfect fit.




First things first - the bra band is designed to provide the majority of support, not the straps as we often believe. Bra straps are there to shape your breasts and ensure that the cups lie flat against your chest. Knowing your proper band size is the most essential step in finding the perfect bra, as it will dramatically improve the performance of the garment.


Ideally, bands should fit snugly around your torso and sit straight and level. If it digs into your sides, gapes, puckers, or rides up too high, it’s probably a sign that you’re not wearing the right size. Another sign is if the straps of your bra are digging into your shoulders, as this is an indicator that they are doing all the work in supporting the breasts, instead of the band.


And how do you get with the band?


(source: biggerbras)



1. Use a measuring tape to measure around your torso just below your bust, right where your bra band would sit. Make sure the measuring tape is level and snug. Round to the nearest whole number.


2. If the number you rounded to is even, add four inches. If it’s odd, add 5. That number will tell you your band size. For example, If someone’s torso measured in at 30.2 inches, their band size would be 34.


We know it sounds a little complicated, but knowing your real bra size is an essential part of the bra-fitting process. However, if you’re short on patience or don’t own a measuring tape, any local bra shop employee can help you figure this out.


Another helpful tip for trying on bras is to make sure the band fits snugly around your torso when hooked on the farthest clasp. The reason for this is that bras (like all spandex garments) stretch out over time, so as the band starts to stretch you can begin to hook your bra onto the tighter clasps, increasing the lifespan of your garment.


Finding your cup size = more math


Underwire digging into your breasts? Saggy and wrinkled cups? Pillowing? These are all signs you’re wearing the wrong cup size. The good news is there’s a way to remedy these situations. We promise this will be the last of the math.


To find your cup size, you’ll need to pull out your measuring tape one last time.

  1. While braless or wearing an unlined bra, measure around the fullest part of your bust. Ensure the measuring tape is parallel to the ground and wrapped snugly around you.
  2. Round to the nearest whole number, subtract your band size (which we measured previously) and refer to the chart above to find your size. For example, 37 inches - 34 inches = 3 inches. In this case, this person would be a 34C.




(Source: liveabout)




As we mentioned previously, bra straps aren’t essential for supporting your breasts- they play an important role in shaping them. The straps for women with fuller chests can be very helpful in making sure that the cups of the bra sit flush to your body, creating a smooth transition between skin and bra. Ideally, the straps should be taught, but not to the point of being painful or uncomfortable. You don’t want them digging into your shoulder, but loosening them too much is no good either because it might cause the cups to pucker or the straps to slip off your shoulders. A good rule of thumb is that you should be able to fit 2 fingers under your bra strap without the rest of the bra shifting out of place. This ensures that the straps fulfill their purpose without digging into your skin. We all know can be extremely painful and uncomfortable.


What are sister sizes?
(source: Cosmopolitan)




We all know that the fashion industry is infamous for variation in sizing, fit and cut, especially in women’s fashion. One brand’s Small t-shirt is another’s Large, a size 0 in Europe might be a size 6 is Canada, and don’t even get us started on the fluctuation in the sizing of jeans. The same goes for bras.


It’s almost inevitable that you’ll find, for example, a 34D in one store doesn’t quite fit the same as a 34D in another. Each brand has its own unique sample size and grading system that make this a very common issue, which is why most lingerie and undergarment experts say that it’s very useful to know what your “sister size” is.


Using the example above, if you’re a 34D in most brands but you feel like a bra you’re trying on is a little too big for you, you might be inclined to try out a 34C. Which isn’t entirely wrong, but that also wouldn’t be your “sister size”.


To find your sister size, if you size up in the band you’ll want to size down in the cup and vice versa. So if you are usually a 34D and wanted to try a larger band size, go for a 36 C, or if you feel you need a larger cup, go for a 32DD. If this is making your mind spin a little, you’re not alone, but knowing what your sister size is can be very helpful when you’re shopping at new stores. Or if you have a bra size that is hard to come by, such as ones with very small bands and larger cups or small cups and larger bands, shopping in your sister size might make bras easier to find.



Miriam Baker is proud to bring you this blog post. We design clothes for women with fuller busts in the heart of downtown Toronto. If you would like to learn more about the brand and the designer behind it, read Meet the Designer for more insight, or sign up to our newsletter for new drops, offers and events. Please contact us at with any stories of your own that are pertinent to our mission or connect with us on Facebook and Instagram. We would love to hear from you!

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1 comment

Awesome and informative. Thank you for this article.


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