Getting proper measurements for your correct bra size will alleviate much of the pain and discomfort you feel while wearing an ill-fitting bra. Persistent back, neck and shoulder pain, constant adjusting of the bra and straps that feel painfully tight, are all signs that you are not wearing a bra that is your size. With a bra that fits properly, you will have more confidence that you are getting the support you need.
Measure the band size by wrapping the measuring tape around your upper back, under your armpits and across your chest above your breasts. As you measure, hold the tape parallel to the ground. If you come up with an odd number, round it up by one inch. For instance, 35 inches should be rounded up to 36 inches for the band size. Write down your measurement on a piece of paper.
Wrap the measuring tape around your back and over the largest part of your breasts, keeping the tape level with the ground as you do so. Write down this measurement on a piece of paper.
Subtract your first measurement by your second measurement and write it down on a piece of paper. For every inch, you will go up one cup size. For instance, if the difference between the two measurements is one inch, then you wear an A cup, or for three inches, you wear a C cup.