How do you calculate bra size?

To calculate bra size, first measure your band size by wrapping a measuring tape around your ribcage just under your bust and rounding to the nearest whole number. Next, measure your bust size by measuring around the fullest part of your breasts. Subtract the band size from the bust measurement; each inch difference corresponds to a cup size (e.g., 1 inch = A, 2 inches = B, etc.). Combine the band size with the cup size to determine your bra size (e.g., 34B).