Glasses size guide: How to find the correct size for your glasses

What do the numbers on glasses mean?

You might have seen that every pair of glasses has a measurement for the frame on the inside of the arms. But have you ever wondered what the numbers on the inside of our glasses actually mean?

The first number represents the width of the lens, the second number is the width of the bridge, and the third number represents the length of the arms.

Knowing this information will help you if you’re interested in buying a pair of glasses that are the same size as a current frame you already own, as well as helping you find the size of your glasses when buying a new pair online.

Lens width

Lens width on glasses refers to the width of your lenses in millimetres, measured from one side to the other. This may also be referred to as eye size.

To ensure that your frames fit your eyes properly, this measurement is often considered the most useful when choosing glasses that fit you.

Bridge width

Bridge width on glasses refers to the shortest distance between the two lenses in your frames, in millimetres.

Narrower noses can wear glasses with a smaller bridge width, whereas wider noses feel more comfortable with glasses with a bigger bridge width.

Arm length

The arms of your glasses, also known as the temples, run from the front of the frames to just behind your ears, and are measured in millimetres.

For your frames to fit securely and comfortably on your face, and not fall off, the temples of your glasses need to be the proper length.

Compare the numbers on a frame you already own to the numbers displayed on our frames, to ensure a precise and comfortable fit.

How to measure your face for glasses

There are a number of ways to measure your face for glasses. We’ve listed the two simplest ways that you can measure your face yourself at home.

The ruler method

• Hold the ruler parallel to your temples in front of a mirror.

• Measure the distance between your temples in millimeters (mm).

• If you need to convert your measured value to millimeters, multiply it by 25.4

After you've measured your face, figure out the total frame width of the glasses you want. This is the sum of the lens width and the bridge width. Your frame size may differ by 3mm from your measurement. Simply select a frame size that corresponds to the length of your face.

The credit card method

The short edge of a standard-size credit card is approximately 54 mm long. You can get a general idea of what size your face is by placing this edge against your face.

Simply place the credit card underneath your eye with the long edge running parallel with the bridge of your nose.

• Choose smaller frames with narrower lens widths, if the card's edge extends past the edge of your eye.

• Choose medium frames with regular lens widths, if the card's edge is aligned with the outside corner of your eye.

• Choose larger frames with wider lens widths, if the card doesn't reach the outside corner of your eye.

GLAS glasses size guide

We are aware that each face is unique, and we create iconic frames to accommodate all types of faces, from small to large. Face shape also plays a role in choosing glasses that suit you. Click here to read our face shape guide to determine your face shape.

When it comes to building your own personal glasses wardrobe, our glasses size guide helps you pick from our assortment of reading glasses.

The precise frame measurements unique to each of our products are listed on the individual product pages. You can see our general size recommendations below.

Small glasses

Our smaller glasses have a lens width between 42mm to 48mm.

Our smaller glasses have a bridge width between 14mm to 17mm.

Medium glasses

Our medium glasses have a lens width between 49mm and 52mm.

Our medium glasses have a bridge width between 18mm and 19mm.

Large glasses

Our large glasses have a lens width of 53mm or wider.

Our large glasses have a bridge width between 20mm and 22mm.