What Do the Numbers on Your Glasses Mean? A Complete Guide

April 07, 2025

Lucent Optical

The little numbers printed inside your frames often go unnoticed. But do you know they carry useful information about your glasses?

Yes, these numbers denote different helpful measures, including lens width, bridge width, and temple length. It is important to understand these numbers and how they affect vision and comfort.

In this guide, we'll understand all these numbers and their significance for a comfortable fit and style. Moreover, we'll also discuss how to use these numbers while buying glasses.

Why the Numbers on Glasses Matter

It is crucial to understand that the numbers on your glasses are significantly important. The correct set of numbers assures that the pair is perfect for you, ensuring style, comfort, and performance altogether.

If you understand these numbers properly, online eyeglasses purchasing will become much more convenient. Moreover, it is also beneficial to adjust your current pair for a perfect fit and performance.

Breaking Down the Numbers on Your Glasses

Lens Width: The horizontal width of each lens (e.g., 52mm).
Bridge Width: The distance between the lenses (e.g., 18mm).
Temple Length: The length of the arms that rest on your ears (e.g., 140mm).

How to Find the Numbers on Your Glasses

Are you wondering how to find these numbers on your glasses?

These numbers are usually found inside the temple arm and sometimes on the bridge. They are present in a very small font.

If the numbers are faded, you can use a magnifying glass or a bright light to help. If they are completely unreadable, you can refer to the original case of your glasses.

However, here are some useful tips that you can follow to read faded or unreadable numbers.

Focus on the numbers with a flashlight to make them clearer.
Using magnifying glasses can be helpful by making them bigger and clearer.
Check the glasses case. They can also have these numbers.
Check both temples. One side may be faded, but the other has clear numbers.

How These Numbers Affect Fit and Comfort

These three separate numbers are vital in a perfect fit, comfort, and performance.

Here is a brief breakdown of how each of these three numbers can affect fit and, eventually, vision.

Lens width defines how the eyeglasses will sit on your face. It should neither be too wide nor too narrow.
Bridge width determines how the glasses sit on your nose. The quality of a perfect bridge width is that they don't slip or drop.
Temple length ensures that the arms are well-aligned and don't slide off. The right temples must fit perfectly along the sides of your head, or else you will experience discomfort.

How to Use These Numbers When Buying Glasses

Understanding these numbers isn't enough if you are not using them while purchasing new eyeglasses. If utilized smartly, these numbers can readily improve comfort and vision.

If your existing glasses are your favorite because of their perfect fit and comfort, compare their lens width, bridge width, and temple length with your new frames. This not only ensures that you are buying the perfect glasses but also ensures the same comfort level.

If you want to change the style, for instance, if you want to get oversized frames, it may require little adjustments in these numbers.

Larger frames have larger widths, and to fit perfectly, you may need the one with a wider bridge.

While switching the frame style, if you are unsure, it is always recommended to consult an optician to get the best pair with the perfect size.

Additional Numbers on Prescription Glasses

Other than the frame measurements, there are additional numbers on prescription eyeglasses. Some of the most important numbers include:

Sphere (SPH) measures the strength of your lenses for shortsightedness or long-sightedness.
Cylinder (CYL) and Axis measure the degree and direction required for astigmatism correction.
Pupillary Distance (PD) measures the distance between the centers of your pupils. It ensures that the lenses are perfectly aligned and clear vision.

Conclusion

The numbers on your glasses can help you find the perfect prescription eyeglasses that improve your vision and enhance comfort. The frame measurements need to be critically considered to ensure a comfortable fit.

Knowing and understanding these numbers can help you purchase the right pair of glasses online without any inconvenience.

If you are confused and unsure, visiting an optician is recommended and can help you with expert guidance. Other than these numbers, some significant prescription numbers are essential for clear and enhanced vision.

Pay attention to these little yet significant details to stay confident and comfortable with enhanced vision. The right pair of eyeglasses can make a huge difference.