I'm guessing from this question that you:
A) are trying to guess your girlfriend's size to get her some sexy lingerie for Christmas
B) are going to be a contestant in some kind of tit judging event
C) have way too much time on your hands
But, since you must know, I'll tell you -
Cup size is determined by first measuring around right under the boobs. Now, if this number is under 33", say 31", you add 5" to that, coming up with 36". But, if this under-bust measurement is 34", then you only add 3", coming up with 37", but since it's an odd number, you round up 1" to make it 38". Still with me?
Ok - then, you take another measurement, this time all around from the fullest part of the breast. You then take that number, say it's 40", then subtract the underbust total, say 36", and the difference, 4", is what determines CUP size. Then you've got your band and CUP size = 36D
1" = A
2" = B
3" = C
4" = D
As you can see, this is not an easy process even with a tape measure, let alone eyeballin' it. take care DB
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