Bra sizes are confusing, here’s why

Let’s be honest, bras are confusing. There are thousands of brands, hundreds of bra sizes and dozens of styles. So how do you find the right bra that actually fits?

The big scary stat out there is that apparently 80% of women are wearing the wrong bra size! So even before we start bra shopping we kind of feel like we’ve lost.

No standardized bra sizes…sigh

Finding the right sized bra is hard. There is no standardized bra sizing between brands, and the way bra sizes are related to one another is confusing, not to mention that every country has a different size structure.

The cup is measured by volume, and confusingly that volume can stay the same as you move down a band size and up a cup size, or up a band size and down a cup size. This is called sister sizing, and it means that, a 34C could have a similar volume to a 32D or 36B. Bras also fit differently based on the shape of the bra and the band measurements, how your breast volume is distributed on your body and again, by brand.

With all of those variables at play, it will surprise you to find the size that works best for you may be pretty different from what you’re wearing, hence the 80% stat mentioned above.

Just take a look at the site What Bra Sizes Look Like, which displays photos submitted by visitors to show how different bra sizes can look. Some may surprise you!

So how do we find a bra that fits?

The best thing to do is to measure yourself at home and always refer to the sizing charts that have been created by your chosen brand. Here's ours!

Or you can try this bra size calculator the subreddit /r/ABraThatFits, at home. Subreddit members created the calculator in 2014 using professional bra-fitting metrics, personal experience, and user feedback. Subreddit moderators continue to update it regularly.

The online tool takes multiple measurements into account, including your bust and under bust size while lying down and bending over, to calculate bra sizes according to the US, UK, EU, Australian, French, and Japanese systems. Remember though that any measurement is just a starting point and doesn’t guarantee a perfect fit.

Try-on tips

Back band

The band should be snug and ideally with a few fingers’ worth of room at the back. If you can stretch the band a lot, try a smaller band size. Fit the bra initially on the loosest hook so you can tighten it as the material stretches over time.

OR if you want a back band that will adjust with your body, Infiniti Bra has you covered HERE!

The band should sit parallel to the floor and not ride up. If the band moves up when you raise your hands above your head it may be too big and if it feels uncomfortably tight then it probably is.


Straps should be reasonably snug, not digging in or falling off. And larger busts should opt for thicker straps. 

Infiniti Bra has slightly larger straps than average to make things a lot more comfortable and supportive, they can also be adjusted from the front!

Underwire bras

The center piece that joins the two cups should lie flat on the center of your chest. Wires should not float off your chest, sit on the breasts, or dig into your sides. If they do, try a larger cup size.

If you are pregnant or breastfeeding it may be wise to opt for a non wired bra so that you are comfortable and so the underwire does not dig into your ribs or cause issues when your milk supply comes in.

Infiniti Bra's pumping and nursing cups are non wired and molded to help with support and make your boobs look beautiful!


Cups should contain the breasts evenly, without creating spillage or cutting into the top part of your chest. Gaping may mean you need a different cup size. Baggy or wrinkled cups are a sign that a bra is too big. Spilling over the top and sides is a sign that a cup is too small.

So, measure yourself or get measured by a professional, and don’t get hung up on the numbers and letters on the label, or in Infiniti Bra's sizing case, flower names. Your right size is what really fits you and makes you feel comfortable. And remember that your breast size will fluctuate throughout the month, read more about that in our ‘boobs are amazing and unique’ blog.

We hope you enjoyed this blog and that you can now feel more confident to find a bra that fits. We would love to hear where you found your perfect bra or even if you even got that far?