Measuring your eyeglass frames correctly allows you to order a replacement frame that will fit your lenses. Frames have four measurements that determine the overall shape and size. The eye size is the width of the lenses; the vertical measurement is the height of the lenses; temple length determines how they sit on your ears; the bridge size accommodates your nose.
Take off your eyeglasses and fold both temples in. Lay the glasses on a flat surface with the lenses facing up.
Place a sheet of paper vertically on the interior of the right lens where it meets the bridge in the center of the glasses.
Place a second sheet of paper vertically on the right side of the right lens, aligning it on the widest part of the lens where it meets the frame.
Measure the distance in millimeters between the two pieces of paper. This is the eye size for your eyeglass frames.