Glasses size measurements: A guide to eyeglasses frame size
Just because a pair of eyeglasses looks great on display in an optical store doesn't mean it will fit well, feel comfortable and look great on you.
There are many different eyeglass sizes and your frames should be fitted by a skilled optician to ensure the best fit, comfort and appearance.
Eyeglass sizes typically are stamped on the inside of the temples of the frames to help you select the best-fitting glasses for your head size and facial features. (Read more about eyeglass frame sizes.)
Generally, the best eyeglass sizes will result in the following fitting characteristics:
Your eyes are centered (or nearly centered) in the lens opening of the frame.
The weight of the frame is evenly distributed across the bridge of your nose (or equally distributed onto the two nose pads of the frame).
The frame temples gently touch (or nearly touch) the sides of your head, without any significant pressure or a large gap between the frame and your head.
The temples are long enough to extend beyond your ears so the ends can be adjusted to conform to the contour of your head behind your ears for a secure, comfortable fit.
You should be able to bend forward, look straight down at the floor, and shake your head without your glasses slipping or sliding out of position.
Eyeglasses that are the correct size may still need to be adjusted to fit properly. For example, if your glasses are sliding off your nose, your optician or your eye doctor can adjust the temples or replace the nose pads to improve the fit and comfort of your eyewear.