Bra Size Calculator
Find your correct bra size with two simple measurements. Measure your underbust (band) and bust circumference, and this calculator determines your band size, cup size, and sister sizes in US, UK, or EU sizing systems. An estimated 80% of women wear the wrong bra size.
How to measure:
- Band (underbust): Wrap a tape measure snugly around your ribcage, directly under your bust. Keep it level and breathe normally.
- Bust: Measure around the fullest part of your bust. Do not compress. Keep the tape level.
The cup size is determined by the difference between bust and band:
- 0" = AA | 1" = A | 2" = B | 3" = C | 4" = D | 5" = DD | 6" = DDD/F
Sister sizes have the same cup volume but different band sizes. Going up a band size means going down a cup letter, and vice versa.