TH 2026

Sunglasses and Eyeglasses Size Guide

Choosing the correct eyewear size can be a frustrating and uncertain experience, as identifying the perfect frame goes beyond simple style selection. Factors such as face shape, bridge size for a comfortable nasal fit and temple length for optimal stability are crucial elements for finding the right fit. 

Fortunately, you don't have to navigate these complexities alone. Our comprehensive eyewear dimensions guide breaks down key frame measurements, empowering you to confidently select the dimensions that best suit your needs. 

How to read glasses size?

You have likely noticed a series of small numbers engraved on the inside of the temple arm and wondered what they mean. These figures are the key to how to read glasses size correctly; they indicate the precise frame dimensions.

The first two numbers indicate the lens width (also known as caliber) and the bridge width. The third number indicates the temple length. These values are always displayed in this specific order and measured in millimeters (mm) for international accuracy.

Lens Width (Caliber): This is the horizontal width of just one lens at its widest point. It’s the most important number for determining the overall fit and style of your frames.

Bridge Width: This is the distance between the two lenses. It represents the part that rests on your nose, ensuring your glasses stay comfortably in place without slipping.

Temple Length: This is the total length of the arms of the glasses, measured from the hinge to the very tip that curves behind your ear for a secure fit.

How to find the perfect fit?

If you don't have your current frames nearby or if this is your first purchase, don't worry. You can easily determine which size is perfect for you. Follow the steps below to find your fit:

STEP 1 Take any credit, debit, or loyalty card	STEP 2 Stand in front of a mirror, hold the card steady and align one edge with the center of your nose

Now all you have to do is checking the position of the card. The size you should choose is determined based on where the opposite edge of the card aligns with your eye.

SMALL SIZE	MEDIUM SIZE	LARGE SIZE
Card edge extends past the corner of your eye? Choose a Small size. In terms of prescription glasses, we recommend frames with a lens width up to 47mm. For sunglasses, go for a maximum of 52mm	Card edge aligns with the corner of your eye? Choose a Medium size. In terms of prescription glasses, we recommend frames with a lens width ranging from 48 to 51mm. For sunglasses, go for a width ranging from 53 to 56mm	Card edge ends before the corner of your eye? Choose a Large size. In terms of prescription glasses, we recommend frames with a lens width of 52mm and up. For sunglasses, go for a width of 57mm and up

Need a second opinion?

Don’t leave your comfort to chance. If you're stuck between sizes, reach out to our dedicated Customer Service team. Whether through a phone call (+39 015 20479) or at info@otticanet.it, our experts will help you decode the measurements and find the frames that best complement your features.