First, put on an unpadded, wired bra and grab a cloth measuring tape. Stand in front of a mirror and wrap the tape around your back at the band level. Keep it straight and measure just above your bust where the straps meet the cups. The band provides most of your bra's support, so be sure to pull the tape measure tight against your back. If you land on an odd number, round down to the nearest even number. This is your bra band measurement. Next, keep the tape around your back at band level and hold it more loosely than the other measurement. Measure the fullest part of your bust gently without compressing. If you land on a half inch, round up, and you've found your bust measurement. Plug these two numbers into our bra size calculator, and we'll find your correct size.