Index sizes as of 2015-02-05 18:30:18.547456

Index sizes are a bra sizing system that uses numbers instead of letters.

The goal is to clear out all the confusion between how different brands use different letter sequences for their bras in their various country conversions.

Index sizes use the standard UK/US band sistem, but use numbers 1, 2, 3, 4 for cups starting at A cups.

A = 1
B = 2
C = 3
... and so on

An index size separates bands and cups using the : symbol, examples:

34:8
28:13
36:3

Benefits

Once you know the index size for two bras you can easily know how many cups difference they have by just subtracting the numbers.

Caveats

One consideration to have when using index sizes, is that some brands will use a different increment to cut their different cups.

Most brands will normally use a 1" difference between cup and cup size. So comparing all those should be alright.

A few brands will use a 2cm difference, or some others will use a 4cm difference (Avocado lingerie ) so it is impossible to make an easy comparison between those bras and others.

The best way to overcome this problem is to just do a proper comparison by measurements.