This technique can be effective to find your bra size if you cannot go in store to get help from one of our sales consultant. Remember that each brand is different and therefore your size may vary from one brand to another, (see table of equivalences below).
To take the measurement, use a flexible tape measure, you can take the measurements with or without bra. If you choose to take them with a bra, make sure you are comfortable and that it fits snugly (not too tight or loose), and the straps are adjusted so that your nipples are halfway between your elbows and your shoulders).
Let's start by finding the size of the back band. Face a mirror, measure the circumference of your rib cage under the breast, where the band of your bra is usually located. Make sure the ribbon is parallel to the floor and that it is tight against you (but not too tight) and write the measurement in inches. If you do not get to a specific number, for example, 33 inches and a half, round to the next higher number, so here 34 inches. The bra sizes are calculated by even number, 30-32-34-etc, if ever you reach 33, the sizes 32 or 34 will do according to the brand, but for now, round to the largest, 34 inches.
Then, measure the cup size. Place the measuring tape, always parallel to the floor, around your chest at the height of your nipples to measure the widest part of it. This time, avoid taking the measure too tight on your chest, note the result in inches. Because the size of your breast varies with your menstrual cycle and your hormones, make sure you take the measurement at a time when it is rather normal size. Round the result to the nearest whole number (35.5 inches becomes 36 inches).
Subtract the measurement from the back band from the chest size. The difference between your two results will determine your cup size. A difference of 1 inch = cup A, 2 inches = cup B, 3 inches = cup C, 4 inches = cup D, 5 inches = cup DD or E (according to the mark), 6 inches = cup F or DDD (depending on the brand) and so on.
Combine the result you got for the back band and the cup you just calculated. For example, 34C means 34 inches for the band and a C cup.
Remember that cup size varies depending on the size of the band.
The cap of a bra size 34B will be smaller than a size 36B. If you change the size of the band, you have to change the size of the hat.
If you need a larger band size, instead of 34B, you would choose 36A.
If you need a smaller band size, instead of 34B, you would choose 32C.