Fit Guide

Forget the measuring tape. Start by understanding how bra sizing works and what the right fit should feel like. Our guide gives you the tools you need to fit yourself. It’s easier than you think.


Bra Sizing

Bra sizes are made up of a number and a letter. The number represents your back size and the letter represents the cup size. This letter represents the difference between your back and bust sizes.

Evaluating Fit

There are four main areas to evaluate when finding your perfect fit. Put on your favourite bra and review the checkpoints below to see if it’s the correct size.

Troubleshooting Fit

More solutions to common bra fit problems and help troubleshooting when to move up or down in size.

Sizing Charts

A summary of size conversions for bras, bodysuits, slips and knickers.

Find Your Perfect Fit

Size

Bra Sizing

Bra sizes are made up of an even number and a letter. Back size is represented by a number, which is a tight circumference measurement (in inches) of the upper ribcage just below the bust. The letter indicates cup size, which is the difference (in inches), between the back and bust measurements.


A = 1” difference

B = 2” difference

C = 3” difference

D = 4” difference

DD = 5” difference

E = 6” difference

Ok, here’s where it get’s a little complicated, but stick with us…

Because the cup and back sizes relate directly to each other, you can’t have one without the other. Therefore, one letter represents many different sizes.

Let’s use a size 34D as an example. If that band was to shrink to a 32, but the cups remained the same size, the ratio between the back and the cups would increase from 4 inches, to a difference of 5 inches, making it become a DD. In other words, a 32D is a cup AND band size smaller than a 34D, yet both are still D cups

Here’s the golden rule of bra sizing:

When your band size gets bigger, the cup size gets smaller.

When the back size gets smaller, the cup size gets larger.


Each column in our size chart below represents bras with the same cup size, but different back sizes. Use this to help you navigate through changing sizes according to how your bra fits.

A32A34A36
B30B32B34B36
C30C32C34C36
D30D32D34D36
DD30DD32DD34DD36
E30E32E34E36
F30F32F34
Evaluate

Evaluating Fit

There are 4 key parts of your bra that determine fit. Here’s what they are, how they should feel and why. Put on your favourite bra and follow these checkpoints to see if it’s the correct size for you.


1. The Band

The band is the anchor of your bra. It’s where most of the support will come from. It requires a firm fit in order to perform its best.

You should always fit your new bra on the loosest hook and eye setting. This will allow the bra to be tightened (and keep your bra fitting perfectly) as the band starts to get slightly looser after you’ve worn it a few times.

Once your bra is on and fastened to the loosest setting, it should feel comfortably snug and sit perfectly parallel to the floor in the front and the back… even when you shrug your shoulders or move around.

If the band rides up at the back it’s probably too big. Choose a smaller back size and remember to go up a cup size to compensate for the change.

 

2. THE Cups

The cups should fit smoothly. There should be no wrinkling, or this means your cups are too big. There should be no bulging out of the top or sides, or this means your cups are too small.

The ‘wire line’ (the seam where the cup connects to the band) should go right around the contour of your breast, sitting flat against your ribs without digging in to your breast tissue.

If it’s lifting away from your body, the cups may be too small. Try going up a cup size.

If the cups are extending to far across your back, the cups may be too big.   Try going down a cup size.

 

3. THE BRIDGE

The center front gore that sits between the breasts also called the bridge.

The bridge of wire bras should fit flat against the body.

For wireless bras, it’s ok if it lifts away from the body only at the center.

If there’s a gap between the bridge and your sternum, or it’s sitting on top of your breasts, it might mean that the cup size is too small. Try to go up a cup size, but keep the same band size.

 

4. THE STRAPS

Since the band is the main source of support, your straps only need to rest on your shoulders.

If the straps are digging in or you’re feeling strain on your shoulders, it might be a sign that the under bust band is too big and not giving enough support.

Try a smaller under bust size and a cup size bigger.

If the straps, after being adjusted, are slipping down your shoulders it might mean that your band size is too small. Try going up a band size and down a cup size to compensate.

Adjust

Troubleshooting Fit

Bra Cups Puckering?
Your cup size is too large. Go down one cup size or tighten your bra straps.

Bulging out of the top or sides of your bra cups?
Your cup size is either too small or cut too low for the size of your breasts. Try going up a cup size (e.g.: from a B cup to a C cup) or choose a bra style that has more fabric in the cup for example, a Classic bra, Balconette or Longline rather than a Demi Cup.

One cup fits fine, but the other cup puckers?
One breast is larger than the other. This is very common, but you should always fit to the larger cup. Sometimes you can adjust the straps or try different fabrics, this may help hide the difference.

Underwires tip away from your body?
Your bra cups are not deep enough. Try a larger cup size.

Bra riding up in the back?
Your band size is too large. Try going down a back size.

Shoulder Straps dig into your shoulders?
Your bra is not giving you enough support. Try going down a back size for a snugger more supportive band.

Navigating Size Changes

How To Change Sizes Depending On Your Fitting Needs


The back size is too small, but the cup size fits perfectly

Go up a back size and down a cup size

The back size fits perfectly, but the cup size is either too big or small

Keep the same back size, but go up or down a cup size accordingly

The back size and the cup size are both too small

Go up a back size

The back size and the cup size are too big

Go down a back size

The back size is too big and the cup size is too small

Go down a back size and up two cup sizes

The back is too small and the cups are too big

Go up a back size and down two cup sizes

Charts

Sizing Charts

A summary of size conversions for bras, bodysuits, slips and knickers.


BODYSUIT & SLIP SIZES
FORTNIGHTBRA SIZEDRESS SIZE
SA/B/C/D 30-32. A/B 340-4
MDD/E/F 30/32. C/D 34. B/C366-8
LDD/E 34. D/DD 3610
XLDD/E 34. D/DD 3612-14
INTERNATIONAL BRA BAND SIZES
FORTNIGHTUKNORTH AMERICAEUROPEFRANCEITALYAUSTRALIAJAPAN
30303065800665
32323270851870
343434759021075
363636809531280
3838388510041485
INTERNATIONAL CUP SIZES
FORTNIGHTUKNORTH AMERICAEUROPEFRANCEITALYAUSTRALIAJAPAN
AAAAAAAA
BBBBBBBB
CCCCCCCC
DDDDDDDD
DDDDDD or EEEDDDDE
EEDDD or FFFFFF
FFGGGFFG
KNICKER SIZING
FORTNIGHTSMLXL
NORTH AMERICA0-46-810-1214-16
UK4-810-1214-1618-20
FRANCE32-3638-4042-4446-48
ITALY36-4042-4446-4850-52
DENMARK30-3436-3840-4244-46
JAPAN3-79-1113-1517-19
AUSTRALIA4-810-1214-1618-20
RUSSIA38-4244-4648-5052-54
GERMANY30-3436-3840-4244-46
*JEAN SIZE24-2526-2830-3232-34

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