How eyeglass sizing works
Did you know that eyeglasses come in a variety of sizes? Men’s and women’s eyeglasses only vary a little in size, but there’s a larger discrepancy between kid’s and adult glasses measurements.
There are three main number measurements that your optician will use to ensure your eyeglass frame fits. These numbers indicate the size of the eyeglass frame’s temples (the earpieces or “arms” of the frame), the bridge (that piece that goes over your nose connecting your to lenses), and the “eye” or lens measurement (the size of the actual eyeglass lens).
For an adult—these measurements may look something like this: 52-19-150. An eyeglass frame with these measurements has lenses that are 52 mm in diameter, a bridge that is 19 mm, and temples that are 150 mm in length.
Although adults can have a wide variety of eyeglass size combinations, each part of the eyeglass size combination falls within a standardized size range. Eyeglass frame lenses vary from 40mm to 60 mm in size. (Though some very over-sized styles or sunglasses may run larger). One’s bridge size can vary from 14 mm all the way to 24 mm, depending on far apart the eyes are set and the width of one’s nose. Though most eyeglass frames only come with a few options in temple length, standard temple size can vary from 120 to 150 mm.
If you shop for your next eyeglass frame online, a general rule of thumb to use is this. Choose a new frame that is close to your current size. (You can often read this size inside the temple of your eyeglass frame.) Opticians suggest that you keep the lens size within 2 mm of your current frame (unless you are intentionally choosing an over-sized style), within 1 millimeter of your current bridge size, and within 5 millimeters of your current frame’s temple size.
For a child, these measurements will be much different. For obvious reasons, many of these measurements will be smaller. A child’s lens size will likely be between 40 and 50mm in diameter. A child’s bridge though, could be similar to that of an adult, a number like 19mm. A child’s temple length will generally be shorter, with many children’s frames coming in temple sizes such as 135mm. A child’s eyeglass frame size could look more like this set of three numbers: 48-19-135.
While these measurements aren’t complicated, it’s always best to have your Eyeglass World optometrist professionally fit you or your child before you order your first pair of glasses. This ensures that the frames you choose and the size you choose will be comfortable to wear and will stay in place.
Have more questions about the size of your glasses or those of your child? Ask an Eyeglass World optician!