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Sister Size

Learn about bra sister sizing
Did you know that the bra cup size is relative to the band size? This means that when a bra's band size is increasing, the relative cup volume is decreasing. And when a bra's band size is decreasing, the relative cup volume is increasing. Because of this, more bra cup sizes can have the same volume, if they do have different band sizes. Bra sizes with about the same cup volume (actual cup size) - even tough they are labeled with different cup sizes - are called "bra sister sizes".

In short: More cup sizes can actually fit your breasts (!) Explore the Bra Sister Sizing system with our sister size chart below.

Bra Sister Size Chart

How to use the bra sister size chart?
Find your bra size in the chart below. Bra sizes marked with the same color (placed in the same row) are sister sizes and do have about the same cup volume (actual cup size) as your usual bra size - and may fit you!
So, if you i.e. are using bra size 34C, a 32D or a 36B may also fit your bust!
30 32 34 36 38 40 42 44
30 A 32AA            
30B 32A 34AA          
30C 32B 34A 36AA        
30D 32C 34B 36A 38AA      
30DD 32D 34C 36B 38A 40AA    
30F 32DDD
34DD 36D 38C 40B 42A 44AA
30G 32F 34DDD
36DD 38D 40C 42B 44A
30H 32G 34F 36DDD
38DD 40D 42C 44B
30I 32H 34G 36F 38DDD
40DD 42D 44C
30J 32I 34H 36G 38F 40DD
42DD 44D
  32J 34I 36H 38G 40F 42DD
    34J 36I 38H 40G 42F 44
      36J 38I 40H 42G 44F
        38J 40I 42H 44G
          40J 42I 44H
            42J 44I

YOUR Experience With Bra Sister Sizing...

Share your own experiences on bra sister sizing. Does it work for you and your burst? Thanks!
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