Glasses frame size guide

You may be thinking that the glasses frames are simply part of the aesthetic, and you’d be partly right. But the frames also contribute to the function of your lenses and the fit is important for ensuring your glasses sit at the right place and are the right size so you don’t get headaches.

Read on for a comprehensive guide to glasses frame sizes and how to choose the right size frame for your face.

What do the numbers on glasses mean?

Example of glasses frame size labeled 47-20-145, indicating lens width, bridge width, and temple length.

When looking at the side of your glasses, you’ll probably notice a series of numbers printed or scribed into one side. These numbers may look nonsensical, but they actually describe the various widths and measurements of your specific frames. They include the lens width, the bridge width, and the temple length – which, when combined, describe your perfect glasses fit.

Diagram of eyeglasses highlighting the lens width, illustrating its measurement.

Lens width

The first number in the sequence is the lens width measurement. This is the horizontal width of each lens at the horizontal centre. The number will typically range between 40 and 60 mm.

Diagram of eyeglasses highlighting the bridge width, illustrating its measurement.

Bridge width

The second number is the bridge width. This is the distance of the bridge of your glasses – the measurement between the two lenses at the horizontal centre line – where your glasses fit on the bridge of your nose. The bridge size ranges from 14mm to 24mm on average.

Diagram of eyeglasses highlighting the temple length, illustrating its measurement.

Temple length

The temple length, also known as the arm length, of your glasses is the third number you’ll find on your glasses. It describes the length from the hinge to the tip of the arm – the part that goes behind your ear. This measurement is usually between 120 and 150 mm long.

Other glasses dimensions to know

There are a couple of other useful measurements that aren’t found on your glasses. These are useful for when you’re measuring different types of lenses such as multifocals. They also help to ensure the best fit of your glasses – not too loose, not too tight, but just right.

Frame width

The frame width measurement is the horizontal width of your glasses frames, measured from their widest points. It's an important factor in finding glasses that fit your face shape – too-wide glasses will slide off your face, too narrow and you are likely to feel pressure on your temples which can cause headaches. It’s important to find a good balance so your glasses look and fit the best they can.

How to choose the right frame size for your face

Choosing the right frames for your face shape can be a fairly long process, but once you’ve got the right fit, your glasses will look great and help correct your vision. Here are some things to consider when choosing the right glasses frames for your face:

  • The right width – Choose a pair of glasses that fit the width of your face in a well-balanced way. Your frames shouldn’t be wider than the width of your face at the temples.
  • The correct height – You don’t want your frames to completely overwhelm your face. Therefore, the top of your glasses should sit no higher than the line of your eyebrows. Additionally, to prevent your glasses from rubbing against your cheeks and causing irritation, the lower edge of the frames shouldn't sit on your cheeks.
  • Nose bridge – You’ll want your glasses to sit comfortably and snugly, but not too snug, on your nose bridge. Some adjustment of the nose pads may be needed which is why having a fitting at your opticians is essential to finding the right fit.
  • Pupillary distance (PD) – This is the distance between your two pupils (the dark circles in your eyes). Some frames might be better suited to your individual PD than others so it will need to be taken into consideration when choosing the right frames.

Glasses size chart

Here at Leightons, we offer a few standard glasses frames sizes to help make finding the right glasses more easily. Refer to this chart to help you find the frames that are the right size for you. The exact measurements might differ from one style to the next, but these sizes encompass most of the frame widths Leightons offers.

Glasses frame size chart displaying various measurements, including lens width, bridge width, and temple length for proper fit.

Find the perfect frames for you

Finding the perfect glasses frames can be a daunting task, but it doesn’t have to be. Visit your local Leightons branch and speak to one of our qualified dispensing opticians for an eye test and style consultation, including a fitting to help find your perfect glasses. We’ll ensure your glasses are correctly measured, the frames you choose fit your head perfectly, and that your glasses are the right size for your face. Book your appointment today.

If you’re looking for more inspiration or information on glasses and how they fit, read our guides on choosing your lenses – for more information about single vision and multifocal lenses – and how should glasses fit – for information to help you work out whether your glasses are fitting your face correctly or not.

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