Condom Size Calculator

This tool converts two measurements into the size printed on a condom box. Enter the erect length and the girth, measured either around with a tape or straight across with a ruler, in inches or centimetres, and it returns the nominal width in millimetres along with the length range to look for. Fit is a practical matter: a condom that is too tight is more likely to break and one that is too loose is more likely to slip off, and either failure ends the protection against pregnancy and infection. Measurements move by a few millimetres from one time to the next and brands are not consistent with each other, so treat the width as a starting point rather than a final answer.