For anyone who has ever headed into a fitting room to try on a bra, you know how difficult and sometimes exacerbating it can be to find a bra that fits properly and offers the support that you need. The reason that bra fitting can be an exercise in frustration, is that many women don’t understand how bra sizing actually works. More specifically, a number of bra wearers are in the dark when it comes to the relationship between cup size and band size.

Many women mistakenly identify their bra size by their cup size. For example, a woman who wears a 16DD bra, might suppose that her breasts are simply a DD. This misconception might lead her to buy bras close to her band size as long as the bra has a DD cup. For someone with a 16DD cup size, for example, she might have some bras that are 14DD and some that are 18DD. The problem with this scenario is that the band size and cup size of a bra are intimately linked when it comes to a bra’s fit, and the band size is just as important as cup size.

To understand why band size and cup size are both equally important when it comes to finding the right bra, you’ll first need to understand how to correctly measure yourself for a bra.


How to Measure Yourself for a Bra

A bra size is determined by two different, but equally important measurements. The first, is the band size. Band size is the measurement, in centimetres, of your rib cage. To attain this measurement, use a measuring tape to measure the circumference of your rib cage. Place the measuring tape just under your bust, at the narrowest part of your ribs and in a straight line from front to back. This measurement determines your band size.

The second measurement that affects your bra size is your cup size. To measure your cup size, stand straight and measure the circumference around your body at the fullest part of your breasts.

The different between these two measurements determines what sized bra you should be wearing. Using the two measurements above, you can use this size calculator to determine the correct bra size for you.


What You Need to Know About Sister Sizing

There are instances in which you might find yourself stuck for a bra size, and you might be tempted to reach for a size close to the one that you usually wear. Before you do, however, consider the fact that an ill-fitting bra is not only uncomfortable, it can also affect the health of your breasts in the long run.

That’s not to say that there isn’t some wiggle room when it comes to bra sizing. Because bra sizing is determined primarily by volume, there is some overlap in sizing. This overlap is called “sister sizing”.

Sister sizing refers to different bra sizes that support the same breast volume. For example, women who wear a 10DD could also comfortably wear 12D because the breast volume is comparative. She could also get away with a 14C, or even a 16B.

You’ll notice a pattern with sister sizing and that is, whenever you go down a cup size, you go up a band size. This is, again, because bra sizing is determined by volume.


The Blest Bra Difference

At Blest Bras, we specialise in those hard to find sizes for voluptuous women in need of a great fitting bra that offers comfort and support.  With the wide variety of styles, fits and sizes we take all the hassle out of bra shopping and make it easy for you to find the perfect bra for you.

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