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Bra Fitting Guide


Bra Fitting

Have you ever struggled to figure out your bra size? Not sure about the band or cup size or the best style to suit your shape. Don’t worry, around 80% of women are in the same boat as you. Something isn’t fitting right but you can’t put your finger on what it is, well the guide below will help you find your best fit.

It’s important to remember not every style suits every shape, but once you find your best fit you’ll never look back. Make sure you check your size every 6 months, everyone’s body changes but we want to make sure you’re still wearing that best fit for you!

Wearing the right size bra really can make you feel like you can conquer the world.


Band Size

If your band isn’t the right size you might notice it moving up and down your back, the best fitting back band should be parallel to the floor and shouldn’t move.

Top tip - Make sure you’re wearing an unlined or lightly lined bra for these steps, a bralette is fine too.

Grab a soft tape measure (maybe not one from the toolbox) and using the inches side, you need to hold the number 1 in your left hand. Pass the tape measure around your rib cage under your bust (where the underwire sits) and using your right hand take hold of the other side, making both hands meet in the middle under the bust.

Keep that tape measure straight across your back!

That number is your band size. If you land on an odd number like 31 inches, round down to the nearest even number.

Nice and easy, now let's find your cup size!


Cup Size

Top tip – cup size is just as important as the band size, so make sure the current bra you’re wearing doesn’t have any extra push up in, that way you can measure your natural size.

Now you’re going to measure the fullest part of your bust. Keeping that tape measure straight on your back like before, you’re now going to pull it around the fullest part of your bust, giving yourself around an inch of space between the cup and the tape measure.

This number is your cup size. If you don’t land on a whole number just round up. So if you land on 33.5 inches round up to 34 inches.


Calculate That Cup Size

Now you have a number you just need to convert that to a letter. Don’t worry, it isn’t a scientific calculation here, in fact, it's pretty simple. We promise!

Take your band size number and minus it from the cup size number to find out the difference, then using the alphabet find out what letter the number you have represents. So for this case, the difference is 4, and the fourth letter in the alphabet is D.


So just to double-check you have this right feel free to look at our example below.

Band size 31 inches – round down to 30 inches.

Cup size 33.5 inches – round up to 34 inches.

The overall size is 30D

And that’s it! Sweet and simple. Disclaimer though, this isn’t 100% accurate, it’s just a guide.


Check Your Bra Anatomy

Now you have the best fit, let's just check you’re wearing your bra correctly. There are 5 things you should always check. The straps, the centre gore, the fastening (hook and eye) and back band, the wire and the cups themselves.




Make sure your straps don’t fall down your shoulders, equally make sure they’re not too tight so they’re digging in and leaving marks. Your straps should sit firmly on your shoulders with around a one finger gap when pulled on.


Centre Gore

The centre gore should sit flush to you. If it gapes but everything else feels to fit fine, then it’s the style of bra that isn’t suiting you. Balconette bras flatter almost every shape, so if you haven’t tried one then we suggest you do!


Hook and Eye and Back Band

Did you know most of the support of your bra comes from the backband? So it's essential this fits correctly! The hook and eye fastening should be comfortable. If you feel it riding up or down your back then this means the band is too big for you. It should be parallel to the floor and stay put! Try a smaller size, especially if you already have it on the tightest fitting.


The Wire

The underwire of your bra should hold all of your breast tissue. It shouldn’t sit on the breast itself! Make sure the wire is behind all the tissue (essentially in the middle of the armpit) and sitting comfortably.


The Cups

Your breast shouldn’t spill out of the cup, if it does then your cup size is probably too small. Equally, if you feel like you are gaping at the top of the cup then chances are the cup size is probably too big. However, if everywhere fits well but your breast tissue is bottom-heavy maybe from weight loss or breastfeeding then try getting a bra that’s front fastening (racerback) or one with straps you can cross at the back, this will help with that gap you’re experiencing.


Sister Sizing

Sister sizing means you can wear 2 sizes of bra and they should fit exactly the same. You take your original size, so let's say that’s a 34C. You then go up in the back to a 36 and down in the cup to a B. Even though that sister size is a B cup, the cup volume is still the same as the band size has altered by 2 inches.


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