Sister Bra Sizes: Guide & Finder

Sister sizes help you adjust band and cup to keep cup volume similar. Use the finder below to get suggestions.

How Sister Sizes Work

  • Down band → Up cup (e.g., 34C → 32D)
  • Up band → Down cup (e.g., 34C → 36B)
  • Try 1–2 steps to fine-tune support and comfort
  • Check brand variations and use our Bra Calculator for base size

Sister Bra Sizes Finder

Format: band+cup (e.g., 32B, 34DD). Letters only for cup.

Sister sizes adjust band and cup inversely.
Your Size