Properly fitting glasses are essential for comfort and play a key role in achieving optimal visual clarity. Incorrect alignment can lead toward subpar visual clarity, bothersome frame adjustments, and an unbalanced appearance that doesn't enhance your features.

At SportRx, we understand the importance of a perfect fit and it's our mission to help you see better while doing the things you love. Whether you're shopping for glasses online or in-store, our ABO-certified opticians are formally trained in determining an ideal fit. Join us as we reveal how glasses should fit, and what that means for your eyewear.

Table of Contents

A. How Should Glasses Fit?
1. On Ears
2. On Nose
3. Eyebrows
B. Where Should Your Eyes Be In Glasses?
C. Understanding Frame Measurements
D. What's a Better Way of Determining Frame Size?
E. What About Face Shape?
F. 6 Tell-Tale Signs of a Poor Fit & How to Fix Them
G. Shop Prescription Glasses Online at SportRx


How Should Glasses Fit?

Glasses should feel comfortable, make a balanced contact with three points (nose bridge and at the top and/or behind both ears), require minimal readjustments, and optically align with your eyes for an optimal visual experience.

Let's review the points of contact and influential factors when trying on frames.


How Should Glasses Fit On Ears?

The temples are crucial for creating a secure fit. They should extend behind your ears and provide a comfortable grip — without squeezing or pinching. Each temple type presents a unique style. Our guide explains how each should fit.

Skull Temples

Characterized by a gentle curve at the end of the arm, skull temples are one of the most common temple types for glasses. This curve creates a hugging effect, which keeps the glasses securely in place. Sometimes, these are adjustable so you can wrap them more behind the ear.

Determine if your skull temples are the correct length by paying particular attention to the curve. The bend should barely begin at the top of your ear and contour its way back along your skull.

Sketch of glasses with skull temples.

Straight Temples/Bayonet Temples

Often seen in performance frames, straight temples are ideal for fitting seamlessly with helmets and hats. Straight temples, also called bayonet temples, should extend slightly beyond the top of your ears, and create gentle pressure against your skull. There should not be any discomfort or noticeable pressure points.

Sketch of profile view of glasses with straight temples

Cable Temples

The least common type of temples are cable temples. Characterized by a dramatic "C" curve that completely wraps behind your ears, this is the most secure frame. These temple types are most often used for frames designed for extreme sports (i.e., mountaineering), where minimal frame movement is required. It is also a popular choice for those looking for a frame with a little vintage character.

Overall, since cable temples are not adjustable, a perfect length is required for a good fit. They should contour your ears with a snug fit that feels secure, but not tight.

Sketch of profile view of glass with cable temples.


How Should Glasses Fit On Your Nose?

Another important point of contact is where the frame sits on your nose. This is the main determinant of where your prescription lenses will align with your eyes, so a proper fit is crucial.

The weight of your glasses should evenly distribute across your nose. A frame's fixed or adjustable nose pads are irrelevant. Both should feel the same on your nose. You should also feel a balanced weight on both sides of your head and move naturally without experiencing frame slippage.

SportRx Insider Tip: Have a good fit on your nose but want a little extra grip? Consider frames with rubber nose pads that get tackier when wet. Some of our favorite grip technologies are Oakley's Unobtainium®, Costa's Hydrolite, and SMITH's Megol nose pads.


How Should Glasses Fit Eyebrows?

Have you ever disliked the look of a frame on your face, but can't quite put a finger on why? Eyebrows are the culprit. Eyebrows are your secret weapon in determining a good fit. They are also one of the most important factors in how the glasses will look on your face.

Your eyebrows play a big role in showing emotion and communicating through facial expressions. Unless you're trying to achieve a poker face or unibrow, leave the eyebrow-hiding frames on the shelf.

Match eyewear with your eyebrows by looking for a frame that compliments their natural shape. Frames should follow the natural flow of your eyebrows for symmetry. This is how you achieve a flattering fit.

Take a look at the image below and observe where your eyebrows should fit with glasses!

Sketch of 3 faces wearing glasses and showing how glasses should fit with eyebrows. First image is too high, second image is covering eyebrows, and 3rd image is a good fit.


Where Should Your Eyes Be In Glasses?

If you have followed all the previous steps, your frame should perfectly fit and align properly with your face. Now you can ensure that your eyes are optically aligned with prescription lenses. One measurement is needed: your pupillary distance (PD).

Your PD is the distance between your pupils in millimeters, either measured from one pupil to the other or from each pupil to the center of your nose bridge. This measurement tells us where to put the OC (Ocular Center) of the lens in your frame. This is the point where the vast majority of light passes through the lens and is the optically clearest point. Ideally, the OC is located directly in front of your pupils. Your eyes draw naturally to this spot, so if the OC is off, it can create an uncomfortable 'pulling' sensation. Your PD plays a critical role in producing glasses that fit. Fortunately, it's super simple to achieve!

To learn how to easily measure your PD, watch the video below!

Still have questions about PD, or where your eyes should be in glasses? Give us a call! Our friendly team of expert opticians is ready to help — 7 days a week!


Understanding Frame Measurements

While there is a time and place for frame measurements, our opticians learned that they are rarely reliable for determining a good fit. They are important from a manufacturing standpoint, but are misleading as a sole source of information. A basic understanding of frame measurements is helpful only as an additional reference.

Here's a breakdown of the most common frame measurements and a visual representation of where they're taken from a frame:

  • Lens Width: the widest point across the horizontal width of the lens. A frame's eye size often uses this measurement.
  • Lens Height: the tallest point across the vertical height of the lens.
  • Bridge Width: the closest distance between the two lenses. (NOTE: It is not how wide the bridge is or where it makes contact with your nose! This is a common misconception.)
  • Temple Length: total length of the arm, which usually starts at the frame front and ends at the temple tip.

*All frame measurements are always in millimeters.

Sketch of glasses frame with where to locate specific frame measurements.


What's a Better Way of Determining Frame Size?

Traditional frame measurements make a good foundation for understanding a person's frame size, but they are not the best way of determining how a frame will fit.

Instead, we recommend shopping by SportRx Frame Width (SFW), which is a true representation of how a frame will fit. With a single measurement, you'll take the guesswork out of discovering your frame size — once and for all.

Ready to learn your SFW? With a simple and quick measuring process, you'll find your own SFW and apply it toward all frames at sportrx.com. Watch Sunglass Rob put it into action below!


What About Face Shape?

Instead of focusing on face shape (heart, oval, square, etc.), our opticians believe a properly fitting and well-balanced frame is the best way of achieving an attractive look.

Overall, eyewear is all about balance (and clear vision, of course). Don't limit yourself on selecting opposing frame shapes based on your face. There is so much that goes into a frame that can change the look, such as frame material and lens size. If you shy away from a whole category of frames, you could miss out on a winning style.

Moral of the story? Pick what you like! Try styles that speak to you and make you want to wear them. When you have a frame you love, it will change the way you look at glasses. Just ask Sunglass Rob and Eyeglass Tyler. They love frames so much, they made a life out of it!


6 Tell-Tale Signs of a Poor Fit & How To Fix Them

Still feeling unsure about the fit of your glasses? Not to worry. We've got you covered with our six signs of ill-fitting frames. These fool-proof signs will reveal if the frame belongs back on the shelf, or if you can tweak them for a perfect fit.

1. If your glasses hurt the top of your ears, it could be a sign of too much pressure from an improper alignment.

Try taking your glasses to an optician for an adjustment. They will see if the temples are distributing weight unevenly and creating excess pressure at a single point. By adjusting the temples, you'll receive a more balanced and comfortable fit on your ears.

2. If your glasses' nose pads leave marks, your glasses are likely not sitting at the correct location on your nose. Your nose pads may be sitting too high or too low on your face, which results in a tighter fit.

Try adjusting the nose pads to get a wider fit. If your frame does not have adjustable nose pads, then they are likely a improper bridge size or design for your nose.

3. If your glasses arms are too long, a simple adjustment should create the curve you need for a more secure fit.

Try taking your glasses to an optician for an adjustment. They will heat and manipulate the temple arms for better contouring around your ears, thus creating a better fit.

4. If your glasses' arms are too short, your course of action will depend on whether you own the frame yet or not.

Try glasses on in-person before making a purchase, or when shopping online. Use a retailer with a generous return policy like the Sportrx See Better Guarantee. By trying before buying, or having the peace of mind of a simple return process, you can ensure the temples are a proper length. You can then use this frame's temple measurement as a point of reference for future purchases.

If you already own the frame, you can take your glasses to an optician for an adjustment. You can also try straightening the skull temples to straight/bayonet temples. However, this will largely depend on the specific frame for determining if it's a possibility.

5. If your glasses touch your cheeks, the nose pads could be sitting too low on your nose.

Try adjusting the nose pads to lift the frame away from your cheeks. You can also try Asian Fit frames, which are designed with more pronounced nose pads to situate the frame higher up the nose, and off your cheeks. To learn more, visit our blog on What is Asian Fit?.

6. If your glasses are giving you headaches, it may be time to see an optician or optometrist. If it's a new prescription, rest assured that slight discomfort can be expected during the adjustment period. Before giving up on your new Rx, pay attention to the frequency and severity of the headaches. There are myriad reasons as to why a person experiences headaches with glasses, but some of the most common are due to an ill-fitting frame, incorrect prescription, or digital eye strain.

Try speaking with a professional to determine the cause of your headaches. By understanding the source of your headaches, you'll be on your way to a solution that alleviates them.


Shop Prescription Glasses Online at SportRx

Ready to find your best-fitting frame? SportRx has got you covered. When you shop with us, you’ll find video guides and tool tips throughout the build process as you customize the perfect pair of glasses. An answer to all your questions is at your fingertips, and if you want to chat with an expert, contact us. We’ll put you in touch with one of our friendly in-house opticians who can help you build your prescription glasses and get a perfect fit.

Ditch risky online shopping with our See Better Guarantee. Try your glasses for 45 days and if you're not 100% satisfied, send them back. Get a full refund, exchange, or credit towards a better pair. And return shipping? Covered. Get the best prescription glasses and sunglasses online at SportRx today!

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