Sunglasses are made in a wide variety of shapes and sizes. These measurements can be found on the frame itself. The ability to identify the size of your frame allows you to easily shop, purchase and even replace broken or lost sunglasses.
Locate any sets of numbers on your frame. All sunglass frames follow a standard format for printing measurements. There are three sets of numbers to be aware of: eye size, bridge size, and temple length. All are measured in millimeters.
Find the eye size and bridge size. Both of these measurements are printed together, the eye size followed by the bridge size. The numbers will be along the inside of the temple or engraved on the back of the bridge. Sometimes they are separated by a dash or small rectangle. If the numbers have been rubbed off, use a ruler to measure each individual part.
Locate the temple length. It is a three-digit number printed on the inside of the temple. It can be found after the eye and bridge size, or alone.