What do the numbers on your glasses mean? 

• The numbers on your glasses tell you which style and size work best for your face. 
• When you’re shopping for new glasses online, you can use these numbers to find a pair that will be comfortable for you to wear.  
• Lens sizes are usually between 31mm to 60mm wide.  
• If the bridge feels tight, your frames may be too high on your nose. 

Ever noticed those little numbers on the inside of your glasses and wondered what they mean? If you’re a little lost, don’t worry. Understanding the numbers on your glasses frames takes a little know-how – and that’s what we’re here for! 

Take a look now and you’ll notice a series of three numbers that probably looks something like 52□18-145. All those digits and details have so much value – these digits inform what glasses style and size work best for your face. 

In this blog, we’ll explain what those numbers on your glasses mean and you can use them as a reference for effectively finding a new pair of glasses that fit comfortably when you shop online. 

• How to read the numbers on your glasses
• What is glasses lens width?
• What is glasses bridge width?
• What is glasses arm length?
• How the numbers on your glasses can help you shop online
• Shop your favourite looks with Virtual Try On

How to read the numbers on your glasses

If you already own a pair of glasses or sunglasses, you’ll see a series of numbers on the inside of your glasses’ temples or bridge: 

• The temples are the arms that extend and hook behind your ears to secure your glasses on your face 
• The bridge sits on your nose and connects the gap between your glasses lenses 

Basically, those numbers refer to your glasses frame measurements in millimeters (mm): 

• The first is the product name or number 
• The second is the lens width 

• The third is the bridge width 
• The fourth is the temple (or arms) length 
• The fifth number in some frames is the lens height 

What is glasses lens width?

Most glasses lens size ranges between 31mm to 60mm wide. If your lens width is: 

• 50mm and under, you have a narrow fit or you prefer modest face coverage from your lenses 
• 51mm to 55mm, you have a medium fit or you prefer more face coverage from your lenses 
• 56mm and above, you have a wide fit or you prefer a large face coverage from your lenses 

What is glasses bridge width?

Glasses bridge fit is key to the comfort of your glasses (acetate frames especially!):  

• If the bridge feels too tight or pinches your nose, your frames might be sitting too high on your face 
• If the bridge is too wide, your frames aren’t likely to sit properly on your nose, and your frames might be sliding down your face all the time 

Generally, metal frames have adjustable nose pads on the bridge, so you can tighten or loosen your nose pads for a better fit.  

Most glasses bridge size ranges between 14 to 23mm. If your bridge width is: 

• 14mm to 16mm, your nose bridge is likely small 
• 17mm to 19mm, your nose bridge is likely medium 
• 20mm to 23mm, your nose bridge is likely wide 

Of course, people from different backgrounds tend to have different nose bridge sizes and the types of glasses bridge fit are: 

• Low bridge fit (also called ‘Asian fit’) between 16 to 18mm – ideal if you have a low nose bridge (the bridge of your nose is level or below your pupils), a wide (or round) face, and high cheekbones 

• High bridge fit between 19 to 21mm – ideal if you have a high nose bridge (the bridge of your nose is above your pupils) and low cheekbones 

Pro tip: if your current frames fit well, using the same bridge width to find a new pair of glasses online can do you a solid and help you get fresh frames that fit. 

What is glasses arm length?

The length of your glasses arms starts from the frame’s hinges to the temple tips. Most temple length ranges between 115mm to 155mm. If your face size (temple to temple measurement) is: 

• Narrow (less than 129mm), your arm length is likely between 135 to 140mm 
• Medium (130 to 139mm), your arm length is likely between 140 to 145mm 
• Wide (over 139mm), your arm length is likely between 150mm or above 

How the numbers on your glasses can help you shop online

Knowing what these numbers mean can make it especially easier for you to buy glasses online. If you already own a pair, you can input these measurements to help you find a perfect fit for your new pair. 

You can also filter for ideal glasses size on any product page: 

• Click ‘Size’ in the filter menu 
• Check off the size you want or enter your glasses measurements 

Shop your favourite looks with Virtual Try On

Ordering the best-looking and best-fitting glasses online is easy. Explore our Virtual Try On Guide to get a feel for the different styles and designs available and discover frames starting from just $9 that fit your face and your budget. 

1. Go to our Virtual Try On Guide page 

2. Click ‘Size’ in the filter menu 

3. Check off the size that fits you or enter your glasses measurements 

Once you’ve picked your frames 

4. Click ‘Add Lenses’ and enter your glasses prescription 

5. Pick your lenses 

6. Head to checkout (find out the deal of the day on our coupon codes page)  

Check out our guide for more tips on how to buy glasses online at Clearly. For advice from our experts, reach out to us 24/7 via chat, email, or phone.

Read more: 

• How to read your eye prescription for glasses or contact lenses
• Glasses size guide: How to measure your frames and face 
• How to buy glasses online 

• Build your own sunnies: How to make frames into prescription sunglasses