If you have a measuring tape take your underbust measurement and the fullest part and put them in to the bra calculator at
http://www.sophisticatedpair.com/bracalculator.htm
It’s the only calculator I find accurate and really recommend it! It will give you your *true* size as well as your *sister sizes*. Bra sizing is never really explained properly so often sister sizes ect are not understood. You will have your true size and will be given two other sizes that will fit and offer support if you prefer a tighter or looser band.
The back band makes a huge difference in the cup it’s self, for example a 32E 34DD and a 36D are actually the same size in the cup, theres no difference in the *size* just in the length of the band. This is why we’re advised not to ask for an end cup size and rather a picture of what result we want.
A 30DD and a 36DD are not the same size in the cup at all and all though the letters DD are there, they are totally different sizes.
I hope this helps ^_^
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