When the time comes to buy a new pair of prescription glasses, there are a few important factors to take into consideration. While you might be aware that you need to think about your options with frame material and lens coatings, there are other elements at play with the construction of your glasses. The numbers found inscribed on the inside of the frames of your glasses, for example, have specific meanings that might be useful to your search. Taking time to understand the importance of these numbers is a great way to make an informed decision when buying glasses.

Take a look at this helpful info surrounding the numbers used on glasses. With a little research, you’ll know everything that you need to know in order to buy a new pair of prescription glasses online.

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Understanding What the Numbers on Your Glasses Mean infographic

The First Number

There are three sets of numbers listed on a pair of glasses or prescription sunglasses. Each has a specific meaning, but all are meant to reflect the size measurements of the glasses. The numbers on the glasses you wear will have different markings than glasses worn by someone who has a head of a different size. The first number listed gives the width of the lenses. For example, you might see a marking of 52, which tells someone looking at the frames that each lens is 52 millimeters in width.

The Second Number

The second measurement relates somewhat to the first. This number is meant to inform about the distance between the lenses. This correlates with the design of the bridge and ensures that the lenses are in the correct position to help aid a person’s eyesight. A marking of 15 in the second position on a pair of glasses frames is meant to showcase that the width between the lenses is 15 millimeters.

The Third Number

The final number listed on the inside of prescription glasses is the length of the temple arm. This is the complete length of the arm from the hinge back until it stretches behind the ear. Typically, this is the largest of the three numbers listed. An average measurement would be about 135, meaning that the entire length of the temple arm is 135 millimeters.

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Exceptions to the Rule

While these numbers are usually the most prominent markings found on the interior of the frames of your glasses, there is a chance you will see other numbers listed. In most cases, these are manufacturer markings to denote specific features of the model. You might see numbers meant to highlight the design of the frames or the type of lens colors used. These numbers will usually be easy to differentiate from the dimensions of the glasses because the codes will usually be larger numbers than the measurements.

How To Use These Numbers

Understanding what these numbers mean can make it a lot easier to order new glasses online. If you have your frames handy, you can simply input the dimensions of your eyewear when placing an order. This guarantees you receive frames that perfectly fit your face.

To order the best possible glasses for your lifestyle, a little preliminary research makes a big difference. Explore the selection at Marvel Optics to get a feel for the different designs available and discover eyewear that fits you in all the right ways.

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Best Prescription Glasses

WileyX Profile

WileyX Profile

The WileyX WorkSight series of frames includes prescription-ready safety glasses. The Profile style has rectangular frames with full rims. Triloid frames and polycarbonate lenses meet the American National Standards Institute Z87.1-2010 high velocity and mass impact requirements and U.S. federal Occupational Safety and Health Administration 1910.133(b)(1)(1) standards. These glasses come with a fold-over case, removable side shields and a drawstring storage pouch.

Profile frames may be available in several color choices such as Gloss Brown Demi, Gloss Green Demi, Matte Hickory Brown, and Matte Black. This eyewear can accommodate single vision, bifocal and progressive lenses. Check the frame size and dimensions to determine whether Wiley X Profile can provide the best fit for daily, occupational or activewear.

ArmourX 6001

ArmourX 6001

Another popular frame style ready for prescription lenses is ArmourX 6001. These plastic glasses with polycarbonate lenses meet ANSI Z87.1 safety standards. Large black rectangle frames wrap around the wearer’s face. While these glasses are compatible with single vision, bifocal or progressive lenses, the base curve may not be the best choice for high Rx lenses.

The 6001 style frames from ArmourX are suitable for on-the-job or activewear. A lightweight frame design is paired with lenses treated to resist dust, fog, reflections and scratches. When fitted with clear or tinted lenses, this eyewear provides protection from ultraviolet rays. This style is popular because it is comfortable and stylish enough to wear inside and outside while doing a wide range of activities.



A double bridge distinguishes Shellshore by Marvel Optics apart from other metal rectangular frames. This small feature draws attention upward toward the browline, which can be helpful for balancing the features of a round, oval, triangle or diamond-shaped face and adding an element of style. These full-rim glasses come in a small size and accommodate single vision lenses.

Rectangle-shaped frames with a double bridge are ideal for oval and oblong face shapes. Check the measurements of these frames to determine whether Shellshore is the right safety prescription glasses style for you. These frames may be available in colors such as blue, gunmetal or jet black.

M-Line Brave

M-Line Brave

Brave frames by M-Line have on-trend vintage styling at an affordable price. These round acetate full-rim glasses have spring hinges. Some versions combine black frame fronts and colored temples. Single vision, bifocal and progressive lenses can all be fitted into these frames, as can high Rx prescriptions. An anti-scratch coating maintains optical clarity for comfortable wear and value.

Check the dimensions of Brave frames to determine whether this style is the best choice for your face. Men and women can both sport this retro style. Choose from several shades such as matte black with navy temples, matte black with red temples and matte black. You can also customize this style with clear or tinted lenses.



One of the most popular prescription frame styles for women is Katelyn by Marvel Optics. These cat-eye full-rim frames are another vintage style updated for modern wear. Plastic frame fronts and temples feature textural details for a unique look. The best online prescription glasses for women are compatible with single vision, bifocal, progressive lenses and high Rx prescriptions.

If you have an oval or pear-shaped face, you may want to consider Katelyn frames. These glasses can be fitted with clear or tinted lenses with an anti-scratch coating for vision correction or sun protection. These glasses come in a medium size. Check the dimensions of this eyewear to determine whether it will provide the best fit. Marvel Optics makes more prescription-ready styles for women.