You Will Need:
- Cloth measuring tape (found at any Michaels/craft shop)
- A mirror (optional but helpful).
- A pen and paper.
Here is a good method to measuring for your bra size.
- Strip down to nothing. No camisoles, no t-shirts, no bras, nothing.
- Lean forward and go as close to parallel with the ground as you can. Remember to breath. Slowly massage your sides and armpits to try to encourage any "armpit fat" back towards the breast tissue.
- Wrap the measuring tape around your back, keeping it even with your breasts, and go across the nipple or the "fullest point". Hold the tape there so that it neither squishes the skin in, nor slides away easily (this can be tricky). Write that measurement down.
- Stand up straight and wrap the measuring tape directly underneath your breasts. Use a mirror to check that it is perfectly parallel to the floor. You want the tape to be TIGHT. Not tight like a corset, but as tight as you can go without shaking. This is your band size. Write that down.
- If you are an odd number you could go up a band size or down depending on your preference. I prefer going down for more support, but if you are particularly bony in the rib area a tight band might be too uncomfortable. So if you get 27" you could be a 26 or a 28 band. More on sub-32 band sizes later.
- Take the band size you come up with (if you are in between, do this for both the lower and higher number) and subtract that number from your bust measurement.
- Each number will be a cup size. 1= A, 2=B, 3=C, 4=D, and so on. Keep in mind that different brands from various countries have different cup size methods, so please be sure to look that up! Some brands have no E-cup, some don't do DD or FF cups, etc. Look up what cups a brand offers and go by that. Highly suggested brands would be pretty much anything on BraStop.
Let's say your underbust measures at 30" and your bust measured at 35". The difference between those two numbers is five, which would put you at a DD cup in many brands. This is not the be all, end all number. You need to try it on first. Remember that for every band size you go down, you go a cup size up. If you normally wear a 34D, you would be a 32DD, a 30E, etc depending on the brand (some brands do not have E cups at all).
If the cup size you come up with using this measurement system is different than what it would be if you just did the normal down a band size, up a cup size calculation, it's best to order several cup sizes online. Return the ones that don't fit. If, for example, you get a 28F, but by your calculations you should be a 28E, order both.
If the band is so tight that it interferes with your breathing, go up a band size. If the band is riding up in the back, go down. It takes a lot of playing around but it's worth it in the end once you figure it out.
Now, in regards to sub-32 band sizes.
Many people will be surprised to learn that they are such a small number and will be concerned about where to buy them. Finding 28 is a little tricky but some sites consistently carry them. Sub-28 though usually has to be special ordered with no returns, so keep that in mind. If you measure as a 24-26 band, see how a 28 fits you and breaks in on you first.
Your band size is supposed to be extremely snug. When you jump up and down, the band should not move at ALL. It should not slide down or up as the day goes by. Another teller is, if the band seems parallel or close to parallel in the morning, but by the time you take your bra off at the end of the day it's not parallel, you need a smaller band. A band size is not meant to rest gently over your skin for decoration, it's supposed to dig its roots in and hold you up. Now, it's not supposed to hurt and you don't want to be poked with underwires, but it probably needs to fit a lot tighter than you are used to.
I will say this: the 28 band was uncomfortably tight at first. It took some getting used to. But now once I'm used to it my 32 bands feel like a joke. They have no support in comparison. If you measure as a sub-32 band size and previously you were wearing something 32+, I suggest buying a 30 band size, getting used to that over a month period, then going another band size down gradually. Switching from a 34 to a 28 can be difficult to adjust to and might scare you off unless/until you're more comfortable with a proper fit.
If you have been wearing a small band for over a month and it still causes you pain after the bra has broken in, it's time to go up in size.
Hope this helps you!