How To Measure Sunglasses: A Simple Guide

Perhaps you’re looking to buy a new pair of shades to add a little bit of jazz to your look, or maybe you just want to replace your old sunglasses or prescription glasses. Aside from the style, do you know what else is important when choosing a new pair of frames?

If you said size, you are absolutely correct! Let’s take a look at why that is. So, let’s not waste any time and get to know how to measure sunglasses!

Importance of The Right Size: What to Know Before Buying

How To Measure right Sunglasses size

Most people, when they find themselves in need of new shades or eyeglasses, do not consider size to be an important deciding factor. In reality, the right size and fit of the frames can make a huge difference in your style and comfort level.

For instance, if your frames are too big for your face, they’ll keep sliding out of place, which is not only uncomfortable but in the case of prescription eyeglasses, will also mess with the power and angle of the lenses. All of this can lead to serious discomfort.

A pair of frames that is too small for you, on the other hand, is also going to be uncomfortable as it might pinch the bridge of your nose, not sit correctly on your ears, and just straight up not provide enough protection or correction.

So, how do you make sure you’re buying the right size of glasses for yourself? It’s easy, you measure them. Not sure where to start? Take a look at this simple handy guide!

Guide To Measuring Sunglasses

tips to measure sunglasses size

Read Frame Measurements

The first and foremost thing you need to do is find the frame measurements and learn how to measure sunglasses using these metrics.

Most of the time, the specific measurements of a frame are given on the inside of the arms, i.e. the parts that go over the temples. There, you will find a set of three values written with dashes in between. For example, 51-91-144.

These numbers are the lens width, bridge width, and temple length of your frames respectively. Aside from these three, there are other parameters of measurement as well. 

In order to better understand this, let’s take a look at these measurement parameters:

i) Lens Width: Refers to the horizontal diameter of the lens at the point where it is the widest.

ii) Bridge Width: Th width of the part that sits atop the nose and joins the two lenses. In other words, the gap between the lenses

iii) Temple Length: The length of the arm that extends over the ear and keeps the frame in place.

These are the three measurements that are usually given on the inside of the arm and are typically enough for you to make an informed decision about what size to buy. Sometimes, there is a fourth value given as well, which is the lens height.

iv) Lens Height: The vertical length of the lenses at the widest point. 

Compare With Your Existing Pair of Sunglasses

Once you have the measurements for the frames you intend to buy, you can compare them with the measurements of the ones you already have.

If your existing frames fit you well, try to find the closest measurements to them in your new frames as well. 

If, however, you feel the need to downsize or upsize a little, adjust accordingly. Also, keep in mind that each pair of frames is different and the measurements to a large extent depend upon the manufacturer.

Manually Measure Your Old Sunglasses

If, for some reason, you aren’t able to find the measurements inscribed o the inner side of the arm of your existing pair of shades, don’t panic. They might have faded away due to wear and tear or some other reason, but there’s nothing to worry about.

What you need to do in this case is take out a good old rule and set about measuring the glasses yourself.

Measure the lens width, bridge width, and temple length as specified above. Make sure to note down the measurements in millimeters. Once you have the numbers, you can use them as a reference for your new frames.

And there you have it! That is all you need to do when trying to find the right size of sunglasses for yourself. 

If you do not have an existing pair of glasses or sunglasses, you can borrow one from a friend, see how that fits you, note the measurements, and then use those as a reference.

Alternatively, you can also try out different pairs at the optometrist’s place and find ones that you find most comfortable and to your liking. Once you have your perfect pair, you can note down the measurements and keep them handy for the future.


The important thing is to know what size is right for you because wearing a pair that doesn’t fit you right is going to cause a lot of problems and discomfort in the long run. And now you know why is it important to understand how to measure sunglasses!

Fortunately, measuring sunglasses is going to be an absolute breeze now that you have this handy guide to help you out!

About Tessa Reynolds

Hey, I'm Tessa. I like to do makeup, especially eye makeup. So, I always take inspiration about how I can do better eye makeup that makes my eyes beautiful. Along with makeup, I'm also a big fan of sunglasses, and I always test new glasses that go with my curly hair.