STEP 1: Under Burst Measurement (Brand Size)
Measure tightly around the body, directly under the bust. Check in a mirror to make sure that the tape is straight across the back.
If this number is odd, then add 3-4 to this number. This is your band size. If your under bust measures 28″ add 4 to get a band size of 32″. If it is 29″ add 3 to also get a band size of 32. In both cases your frame size is 32.
STEP 2: Burst Measurement
Measure directly across the fullest part of the bust over the nipple area (at the physical bust point) with your arms at the sides and standing up straight. Check in the mirror to make sure the tape is straight.
STEP 3: Cup Size
Subtract your BAND SIZE from BURST MEASUREMENT. This difference will determine your cup size. If your measurement difference is:
Up to 1″ larger than BAND size…………………………………………………A
Up to 2″ larger than your frame size…………………………………………………B
Up to 3″ larger than your frame size…………………………………………………C
Up to 4″ larger than your frame size…………………………………………………D
Up to 5″ larger than your frame size…………………………………………………DD/E