Bracupsizes were invented in 1932 while band sizes became popular in the 1940s. For convenience, because of the impracticality of determining the dimensions of each breast, the volume of the bracup, or cupsize, is based on the difference between band length and... This video presents an ultimate guide to the Gcupsize. In it, we discuss what it means to be a Gcupsize, how to measure if you're a Gcup, what are the b... Quora is a place to gain and share knowledge. It's a platform to ask questions and connect with people who contribute unique insights and quality answers. This empowers people to learn from each other and to better understand the world. Our brasize calculator, size conversion chart, and tutorial video guide will teach you how to measure your brasize. Plug your measurements in to get your fit! What is the biggest brasize? Bras in these largest cupsizes: L, M and N are still somewhat of a rarity. Our selection represents both everyday bras in underwire and wire free versions as well as front closure, nursing and maternity bras. A B cupbrasize usually means your bust measurement is about 2 inches larger than your band measurement. It is a common cupsize that can look different across band sizes, such as 30B, 34B, or 38B, because the cup volume changes with the band. To find your bracupsize, take a comfy measurement under the breast, subtract it from the measure of your bust when standing or sitting up fully erect, and find your cupsize in the following table.