- Measure your band size
Wearing your bra, take a snug measurement around your ribcage, directly under your bust and keep level all around. If you get an odd number, round up to the next even number. This is your band size.
- Measure your bust size
Take a loose measurement over the fullest part of your bust, keeping the tape level around your body. If needed, round up to the nearest inch.
- Calculate your cup size
Subtract your band size from your bust size, and use the difference to find your cup size on the chart below.