Measuring Guide
Please note that all measurements should be taken whilst unclothed. To establish a correct bra size you only need to take two measurements as follows

1. Underbust Measurement
Measure under your bust by holding a tape measure straight and firmly around your rib cage, across your back and just beneath your bust.
add 4ins. if the measurement obtained is an even number of inches
add 5ins. if the measurement obtained is an odd number of inches.

(For example, if your underbust measurement is 31ins., add 5ins. to obtain bra size 36, or, if your underbust measurement is 30ins. add 4ins. to obtain bra size 34.)

2. Overbust Measurement
Measure round the fullest part of your bust to determine Cup size. Hold the tape firmly, but not so tight that it flattens you.
If the bust measurement: is:
same as your bra size, your Cup size is A.
1in. more gives Cup size B
2in. more gives Cup size C
3in. more gives Cup size D
4in. more gives Cup size DD
5in. more gives Cup size E
and so on through F, FF and G

An example:
Underbust measurement of
29in. + 5in. = bra size 34
Overbust measurement of
34in. = Cup A