A80 is a cup, and the cup size is 10cm. It means that the upper bust is 90cm, the lower bust is 100cm, the difference between the upper bust and the lower bust is 10cm, and the European size is 36A.

Calculation formula of cup size: cup size = bust-lower bust.

Extended data

In general, A-cups are divided into A-type and AA-type. If the figure obtained by subtracting the bust from the lower bust is about 7.5cm, then the girl's bust is AA-cup. If the figure obtained by subtracting the two is about 10cm, then the girl's bust is A-cup. When wearing underwear, girls with A cups and AA cups can adjust by adjusting the buttons behind the shoulder straps of the bra.

A cup also has a certain size range, not a fixed one. If a cup is described by fruit, it is appropriate to use cherry as a metaphor, and it can also be described by an ordinary girl's small fist.

Baidu Encyclopedia: Cup