Size & Fit Guide

Getting the fit right matters as much as picking the style. Here's how to find your size before you order.

Measuring From Glasses You Already Own

Look inside the arm of a pair you own — you'll usually find three numbers printed there, like 52□18-145:

Lens width (first number, e.g. 52) — width of each lens in millimeters

Bridge width (second number, e.g. 18) — distance between the lenses

Temple length (third number, e.g. 145) — length of the arm from hinge to tip

Match these numbers to the measurements listed on each ATHR product page to find your closest fit.

If You Don't Have a Reference Pair

Narrow face: look for frames with a lens width around 48–51mm

Medium face: 52–55mm

Wide face: 56mm and up

When in doubt, size up slightly — a frame that's a touch too big is more comfortable than one that pinches.

For Prescription Lenses: Pupillary Distance (PD)

PD is the distance between the centers of your pupils, needed to position your lenses correctly.

Find it on a recent prescription from your optometrist, or measure it yourself: look straight ahead in a mirror with a ruler against your brow, and measure from the center of one pupil to the center of the other.

Enter your PD at checkout when adding prescription lenses — if you're not sure, leave a note and we'll follow up before production starts.