3.25 centimeters. The label length and width of Kangshifu mineral water is 3.25 cm, and the common mark size requires CE mark, and the minimum size should not be less than 5mmGS mark, so there is no special requirement for the size. Labels are additional information cards or brands used to identify things. As early as 1700, Europe printed the first batch of labels used on medicines and fabrics as commodity identification.