Choose a band
| Cup | Two down | One down | Your size | One up | Two up |
|---|
"Down" and "up" refer to the band number — moving down a band always pairs with moving up a cup letter, and vice versa, to keep volume roughly constant.
Worked example
Reading a real row
Take a 34D. One step down the band takes you to 32DD; one step up takes you to 36C. Two steps in either direction lands on 30E and 38B. All five of these carry approximately the same cup volume — what changes is how the band itself feels around your ribcage.
Questions
Sister size chart FAQs
Find your size in the middle "Your size" column, then read the columns beside it for the sister sizes one and two steps in each direction.
Shape and proportion drift further from your actual measurements the more steps you take, so most people find the first one or two sister sizes the most useful in practice.
The relationships hold generally, but always check whether the brand's own labelled sizes actually cover the sister size you land on before assuming it's in stock.
Also useful