Band Measurement
Using a measuring tape, take a snug measurement around the rib cage, directly under the bust. If the measurement is an odd number, add 5 inches to determine band size. If the measurement is even, add 6 inches.
Tip: When measuring for band size, place your index finger under the tape measure to allow for body expansion necessary for sitting.
Cup Measurement Using a measuring tape, measure around the fullest part of the bust (do not stretch tape tightly). Then, take the difference between this measurement and the band size measurement to determine the cup size.
If the difference is:
Tip: If the band seems too tight, increase one band size and decrease one cup size. If the band seems too large and rides up in the back, decrease one band size and increase one cup size.
Note: The measurement is just a starting point. Different styles fit differently, and each style must be tried on to assure a proper fit. It is best to measure while wearing an underwire bra.