Eyeglass Frame Size Guide: How to Find Your Perfect Fit

Finding the right frame size is essential for comfortable, great-fitting glasses. Understanding eyewear measurements can help you choose frames that fit your face properly and feel comfortable for everyday wear.

Most glasses include three key measurements printed on the inside of the temple arm, such as: 49-21-140

  • 49mm = Lens Width
  • 21mm = Bridge Width
  • 140mm = Temple Length

Understanding Eyeglass Measurements

Eyeglass measurements help you understand how wide, tall, and long a frame is. Comparing these measurements with a comfortable pair you already own can make it easier to find your ideal fit.

Lens Width

Lens width is the horizontal measurement of each lens at its widest point. In a frame measurement such as "49-21-140," the number 49 represents a lens width of 49 millimeters.

A larger lens width creates a bigger, wider frame appearance, while a smaller lens width creates a smaller and more compact fit.

Diagram showing how to measure eyeglass lens width

Bridge Width

Bridge width measures the distance between the two lenses across the nose. In the example "49-21-140," the number 21 represents a bridge width of 21 millimeters.

Choosing the correct bridge width helps ensure your glasses sit comfortably without feeling too tight or sliding down your nose.

Diagram showing how to measure eyeglass bridge width

Temple Length

Temple length measures the arms of the glasses from the hinge to the end that rests behind your ears. In the measurement example "49-21-140," the number 140 represents the temple length in millimeters.

The correct temple length helps keep your glasses secure and comfortable throughout the day.

Diagram showing how to measure eyeglass temple arm length

Lens Height

Lens height measures the vertical distance from the top to the bottom of each lens. Although it is not usually included in the standard frame measurement numbers, it is an important measurement for certain lens types.

A larger lens height can provide more vertical space, which can be especially helpful for:

  • Progressive lenses
  • Bifocal lenses
  • Customers who prefer more lens coverage
Diagram showing how to measure eyeglass lens height

Frame Width

Frame width measures the total width of the glasses from one side to the other, including both lenses and the bridge.

This measurement helps determine whether a frame matches your overall face width. A properly sized frame should feel comfortable without squeezing your temples or feeling too loose.

Diagram showing how to measure total eyeglass frame width

How to Find Your Glasses Size

The easiest way to find your ideal frame size is to check a pair of glasses you already own that fits comfortably.

Look at the inside of the temple arm for a series of numbers, such as: 49-21-140

You can use these measurements as a reference when choosing your next pair of glasses. While exact measurements do not need to be identical, staying close to your current frame size is usually a good starting point.

Frame Size Recommendations

Frame Size Lens Width Best For
Small Under 50mm Smaller faces and petite frames
Medium 50–54mm Most average face sizes
Large 55mm and above Wider faces or oversized styles

Find Your Perfect Fit

The right frame size improves comfort, appearance, and your overall wearing experience. When choosing your next pair of glasses, consider your current frame measurements, face width, and personal style preferences.

If you are unsure which size is right for you, our team is happy to help you find a comfortable fit.