The first part being a numeral, say 36, and the second being a letter, say D, they together connote the size 36D. And just like our first name alone is incapable of revealing our identity so it is with bra sizing: both the numeral and the letter have an equally important role to play. The numeral of a bra label tells you which approximate size the waist is. Why approximate? This numeral is commonly denoted both in centimetres and inches.
There are two elements to your bra size; the band size ie. A, B, C. You will need a measuring tape to determine your bra size. Band size: Using a soft tape-measure, measure around the ribcage directly under the bust. Be sure the tape is smooth across the back and level with the front. Add 5 to this measurement to obtain your band size.