If in any doubt get yourself fitted properly…

Band Size Step 1

Please measure in inches, keeping the measuring tape horizontal, measure under your bra directly under your bust after breathing out – you want this measurement to be as small as possible but round up to the nearest whole number (inch).


Use the table below to convert the measurement into your band size. The red is a highlighted example.


Chart for Band Size

This is your measurement inches 27 28 29 30 31 32 33 34 35 36 37 38
So this is your band size 30 30 32 32 34 34 36 36 38 38 38 38

Note: After a 38 band, the size should be the closest higher even number to your actual measurement So, 39.5″ is a 40 band. A 40″ measurement is a 40 band.

Cup Size Step 2

Wearing a none padded bra, standing with straight arms at your side (you may need some help here), measure at the fullest part of your bust making sure the tape is horizontal. Round up to the nearest inch.

Here’s an example:
From Step 1: 32.5″ is 33” under measurement = 36″ band size (see highlighted example in table)
From Step 2: 40″ over measurement
Step 3: 40″ – 36″ = 4″ difference or D Cup Size (look difference up in table below)
Example Size is probably a 36D.

Step 3 is a calculation (over – under) = difference. Difference then gives cup size using below table:

Diff Size Diff Size Diff Size
0” – ½” AA 7” F 14” JJ
½” – 1” A 8” FF 15” K
2” B 9” G
3” C 10” GG
4” D 11” H
5” DD 12” HH
6” E 13” J

Note – before ordering try and get the result checked by trying an actual 36D on.


It’s really quite easy to find your bra size, but first, we need to tell you up front, that any bra sizing system where a tape measure is involved will not be totally accurate. The reason? A lot of factors can affect your measurements – the bra you’re wearing, the firmness of your breasts, the broadness of your back, the narrowness of your shoulders. These factors and more can give you a false bra size once you’ve measured yourself.

For women who wear a bra size 38D and larger, using this measuring system as a bra size calculator is frankly a mistake. Instead you should be bra sizing starting with your base bra size and tweaking this size based on what you don’t like about your current bra size.