Bra Measuring Guide

Worried about measuring up? There's no need to be, if you follow these simple instructions.

Lingerie Measuring

Step 1 - Over Bust Measurement

We now need to ensure the correct cup size for you. Referring to the line labelled '1' in the picture above, measure in inches around the fullest part of your bust, usually over the nipples. The tape measure should be loose, but make sure it is straight at the back. This is your Over Bust Measurement.

Step 2 - Back Size

Get an ordinary tape measure and whatever privacy you feel you need. Without any clothes or bra on your top half, and referring to the line labelled '2' in the picture above, measure your rib cage in inches directly under your bust, holding the tape firmly to make sure it doesn't slide down at the back. This is your Back Size.

Step 3 - Bra and Cup Size

To calculate your bra and cup size, you can either follow the instructions and consult the chart below, or use our Bra Size calculator at the bottom of the page.

Add five to the first measurement (your Back Size) to get your bra size. If the number is an odd number, round it up to the next even number. For instance if the first measurement is 26, adding five gives 31 so round the number up to 32 to give the Bra Size. To work out the Cup Size use the difference between your Over Bust Measurement and your Bra Size and check against the chart below.

Difference Cup Size
No Difference A
Up to one inch B
Up to two inches (5 cm) C
Up to three inches (8 cm) D
Up to four inches (10 cm) DD
Up to five inches (13 cm) E
Up to six inches (15 cm) F
Up to seven inches (18 cm) FF
Up to eight inches (20 cm) G

What your bra should look like

This is our 3 step check for the perfect fit:

  1. The strap around your body should be firm but comfortable. When you stand side-on at a mirror, the strap that runs around your body should be horizontal and should not ride up at the back at all.
  2. The wires at the front should lie flat against your rib cage and should not dig in, rub or poke out at the front.
  3. Your breasts should be enclosed in the cups and you should have a smooth line where the fabric at the top of the cup ends and meets your bust. You shouldn't have any ridge or bulging over the top or sides of the cups, even if you are wearing a balconette style or lower cut shape.

Trying on tips

When you are trying a bra on, it's best to start off by fastening it on its loosest hook. This way you will be able to tighten the bra up if it starts to give in the back a bit when you've worn it a few times. Also, remember to adjust the shoulder straps to ensure that they are not too loose. When you've put on a bra, you may need to adjust your breasts to make sure that they are in the cups properly. It's a good idea to try a T-shirt or top over the bra that you are trying so that you can see the shape that style gives you underneath your clothes.

This is a guideline only, the best way to check your size is to try some different bras on and see which feels most comfortable and give you enough support.

Bra Size calculator

Input your measurements from the above steps into the boxes below and click 'Calculate Bra Size' to work out your bra size.

Back Size Over Bust Measurement Your Bra Size