Finding the right frame size is an important part of buying glasses for your child online—and the good news is, it’s easier than you might think. Below is a simple guide to help parents understand glasses measurements and sizes, so you can confidently choose the right eyeglasses or sunglasses for your child’s comfort and clear vision.
To make sure your child’s glasses fit properly, the first step is finding the right frame size for them. The easiest way to start is by checking the measurements on a pair of glasses your child already wears comfortably.
You can usually find these numbers printed on the inside of the temple, also known as the “arm,” of the glasses. The frame size is typically shown as three numbers separated by dashes—such as 48-16-135.
What do frame size numbers mean?
From left to right, the numbers usually tell you the lens width, bridge width, and temple length.
Sometimes a fourth number may also appear on the arm. This usually refers to lens height. All of these measurements are in millimeters.
Key glasses measurements
These measurements help you compare your child’s current glasses with a new frame online. A similar size is usually a good starting point when choosing a comfortable fit.
Lens Width
This is the horizontal width of each lens, measured at its widest point. Also called eye size, it typically ranges from 40mm to 60mm.
Bridge Width
This is the distance between the two lenses. The bridge width is the space where your child’s frame rests against the nose. Bridge size usually ranges from 14mm to 24mm.
Temple Length
This is the length of the temple from the hinge to the temple tip, including the curved part that sits around your child’s ear. Temple length is typically 120mm to 150mm.
Lens Height
This is the vertical height of the lens, measured at the tallest point within the frame. Lens height can be especially important for bifocal or progressive lenses.