Glasses sizes are actually just the measurements of the frame in millimeters. Imagine a box placed around the lens:

To get the size, we measure the distance between and within the boxes. That gives us:

 

  • Lens Width (Eye Size)
  • Bridge Width 
  • Lens Height (B Measure)

The temple length is the length of the temple from from the hinge (where it attaches to the frame front) to the tip.

 

  • Temple Length

Size is printed on the frame

These measurements are usually printed on the frame, on the inside of the temple or behind the bridge.

Some of the measurements may be left out. It’s common to print only the lens width and bridge width, for example.

The formatting varies a bit, but the measurements always appear in the same order.

If a pair of glasses has these measurements…

  • Lens Width: 49
  • Bridge Width: 16
  • Temple Length: 135
  • Lens Height: 40

…below is what you might find printed on the frame.

Lens Width – Bridge Width

49□16
49-16

Lens Width – Bridge Width – Temple Length

49□16 135
49-16-135

Lens Width – Bridge Width – Temple Length – Lens Height

49□16-135 B40
49-16-135 B40
49-16-135-40

What size do you need?

Now you know how sizing works. Let’s figure out what size you need.

Read it off your old pair

If your old frames fit well, then others with the same dimensions will fit pretty well too.

Grab your glasses and look for the size information printed on the frame. 

 

Look it up online

Sometimes the size isn’t printed on the frame, but the brand and model are.

You can use this information to find your frames online. Retailers who carry them will usually list the size.

The model can be:

  • A word: Kate Spade Rebecca
  • A number: Ray-ban 5041

Type this into a search engine and see what you find.

 

If all else fails, measure by hand

Can’t find the size of your current pair? Simply take out a ruler (with millimeters) and measure it yourself. Use the boxing method described above.

 

Adjust for accuracy

Glasses sizes are technically for the lenses, not the frames.

But the lenses extend invisibly into the frames a little ways. That’s how they are held in place. So, they are a little larger than what you can see.

When you are measuring by hand, you have to account for the part of the lens that is invisible.

Use these simple adjustments for a more accurate measurement:

 

For example, let’s say you have plastic frames and you measure by hand:

  • Lens width  48
  • Bridge width  18

 

The actual size you need is:

  • Lens width  49
  • Bridge width  17

 

“I’ve never had a pair that fit me well.”

How frustrating! In this case, you will need to estimate your size.

Even if your old pair fits badly, they can still be useful as a jumping off point.

Put them on and stand in front of a mirror. What would you like to be different about them? Are they too wide? Too tall? Not tall enough?

If you can tell how you’d like them to fit differently, then grab a ruler. Visualize where you’d like the frame to sit, and measure the difference.

Glasses sizes are actually just the measurements of the frame in millimeters. Imagine a box placed around the lens:

To get the size, we measure the distance between and within the boxes. That gives us:

 

  • Lens Width (Eye Size)
  • Bridge Width 
  • Lens Height (B Measure)

The temple length is the length of the temple from from the hinge (where it attaches to the frame front) to the tip.

 

  • Temple Length

Size is printed on the frame

These measurements are usually printed on the frame, on the inside of the temple or behind the bridge.

These measurements are usually printed on the frame, on the inside of the temple or behind the bridge.

Some of the measurements may be left out. It’s common to print only the lens width and bridge width, for example.

The formatting varies a bit, but the measurements always appear in the same order.

If a pair of glasses has these measurements…

  • Lens Width: 49
  • Bridge Width: 16
  • Temple Length: 135
  • Lens Height: 40

…below is what you might find printed on the frame.

Lens Width – Bridge Width

49□16
49-16

Lens Width – Bridge Width – Temple Length

49□16 135
49-16-135

Lens Width – Bridge Width – Temple Length – Lens Height

49□16-135 B40
49-16-135 B40
49-16-135-40

What size do you need?

Now you know how sizing works. Let’s figure out what size you need.

Read it off your old pair

If your old frames fit well, then others with the same dimensions will fit pretty well too.

Grab your glasses and look for the size information printed on the frame.

 

Look it up online

Sometimes the size isn’t printed on the frame, but the brand and model are.

You can use this information to find your frames online. Retailers who carry them will usually list the size.

The model can be:

  • A word: Kate Spade Rebecca
  • A number: Ray-ban 5041

Type this into a search engine and see what you find.

 

If all else fails, measure by hand

Can’t find the size of your current pair? Simply take out a ruler (with millimeters) and measure it yourself. Use the boxing method described above.

 

Adjust for accuracy

Glasses sizes are technically for the lenses, not the frames.

But the lenses extend invisibly into the frames a little ways. That’s how they are held in place. So, they are a little larger than what you can see.

When you are measuring by hand, you have to account for the part of the lens that is invisible.

Use these simple adjustments for a more accurate measurement:

For example, let’s say you have plastic frames and you measure by hand:

  • Lens width  48
  • Bridge width  18

 

The actual size you need is:

  • Lens width  49
  • Bridge width  17

 

“I’ve never had a pair that fit me well.”

How frustrating! In this case, you will need to estimate your size.

Even if your old pair fits badly, they can still be useful as a jumping off point.

Put them on and stand in front of a mirror. What would you like to be different about them? Are they too wide? Too tall? Not tall enough?

If you can tell how you’d like them to fit differently, then grab a ruler. Visualize where you’d like the frame to sit, and measure the difference.

Ready to love your glasses?

See the FramesLearn More

How to Order Home Try-on

1. Click the “Home Try-on: Free” button under any frame to select that frame.

How to order step 1

2. A checkmark will appear when frame is selected. Unclick to remove.

How to order step 2

3. Once 5 frames are selected, Home Try-on is added to Cart.

(Must choose 5).

How to order step 3

4. Checkout to complete your order.

Choose 5 FramesHow it works