How to Tell if Sunglasses Are Polarized

Everyone should own a pair of polarized sunglasses.

They cut down on glare, making it easier to see clearly and reducing strain on your eyes.

While polarized sunglasses are extremely popular, many brands still make non-polarized versions. Some even have unique tints or misleading labels that might convince you you’re buying polarized lenses that will protect your eyes from glare.

Fortunately, you don’t have to take the manufacturer’s word for it. Learn how to tell if sunglasses are polarized, and you can check for yourself. Here’s a simple guide to help you identify polarized lenses and ensure your eyes are properly protected.

How Polarized Sunglasses Work

The enemy

We’re going to go out on a limb here and say you probably already know what polarized sunglasses are. Otherwise, boy, do you Google some random things.

Still, it’ll help you better understand how to tell if glasses are polarized if you first understand how their lenses work.

In short, light waves from the sun may appear to move in a straight line, but they’re actually vibrating all over the place. That changes when they reflect off something. In the case of a horizontal surface, like a body of water, the reflected light takes on a horizontal motion. Our eyes perceive this horizontal motion as glare.    

The Man. The Myth. The Legend.

A French physicist by the name of Etienne-Louis Malus discovered this phenomenon back in 1808, but it wasn’t untilEdward H. Land came along in 1929 that the first polarizing material was introduced. The way his technology works is as simple as it is effective. Lenses are treated with chemicals that only allow in light that travels in a vertical motion. As glare travels horizontally, it can’t make it past the polarized lens.

Alright, with that short explanation out of the way, you’re now ready to understand how to tell if your sunglasses are polarized or not.

5 Ways You Can Tell if Your Sunglasses Are Polarized

There are actually five different ways you can do this depending on your circumstances. No matter what, you should be able to use at least one of these polarized tests to figure out if your sunglasses will effectively protect you from glare.

1. Check the Sticker or Label

Obviously, the first place you should check is the online listing, the box it came in, or any tag that was attached to them. As polarized sunglasses are generally considered superior to their nonpolarized alternatives, most manufacturers will make sure to advertise this advantageous feature.

“Oh, wow. I hadn’t thought of that, Joe!”

Well, I’m just saying. If the manufacturer isn’t advertising polarized lenses, your shades probably don’t have them. Unless they have an even cooler feature (x-ray vision?), limited space would be used to list polarization.

Maybe you got rid of the box or tags, though.

In that case, look for a sticker or label on the lenses. Many manufacturers will include one that can prove their lenses really are polarized in case you don’t take them at their word.

If that sticker is still on the lens, hold your sunglasses in front of you and then turn the stickered lens up at a 60-degree angle while keeping the other lens in place. Now, look through that sticker. If it got darker when you did this, your lenses are polarized. If the sticker stays the same, maybe it’s not too late to regift them?

2. Compare Them to Another Pair

No sticker?

No problem.

If you have another pair of sunglasses that you know are polarized, you can just use those.  

If you need another pair for comparison, we got you.

Hold one pair of sunglasses in front of the other and look through the lenses. You shouldn’t have any trouble seeing through them.

What happens when you rotate one of the pairs 90 degrees while keeping the other in place?

If you can no longer see through both lenses, it’s because you have two pairs of polarized sunglasses.

3. Look at Water

Okay, but what if you don’t already have a pair of polarized sunglasses?

Then, there are still three other polarized tests for determining if they’re the real deal or not.

One simple way to do this is to head to the beach. Or a park with a pond. Or a golf course. Just anywhere with a body of water, really, other than your bathtub.

Assuming it’s a sunny day, put on your sunglasses and look into the water. If your lenses aren’t polarized, you’ll only be able to see the surface and probably a good deal of glare.

On the other hand, if you’re wearing a decedent of Edward H. Land’s invention, you won’t have any glare to contend with. In fact, you should actually be able to see through the water’s surface, down where it’s wetter and, I am reliably informed, life is better.

4. Look at a Reflective Surface

You can do something similar with any reflective surface. Presumably, you have a mirror in your home, but if you don’t because you’re really ugly or something, you can also do this with any other reflective surface. You just need to make sure the reflective surface causes glare. Car windshields and windows at an angle that are out in the sun are both perfect.

If putting on the sunglasses eliminates the glare, you know you have polarized lenses.

5. Look at a Computer Screen

Finally, if it’s raining and going outside for your polarized test isn’t an option and you just can’t wait for the weather to clear for some reason, your computer or phone screen will do.

Like, for example, the one you’re using right now.

For reference, this is what a computer screen looks like.

Try to make the screen as white as possible. If you’re using your computer, pull up a blank word document. If you’re on your mobile device, try Google’s homepage.

Then, put on your sunglasses. Just like before, if you turn your head at a 60-degree angle – ear to shoulder – and the screen dims, you have polarized sunglasses.

Dark Lenses Aren’t Enough

Before we conclude, it’s worth pointing out that dark lenses aren’t enough to defend against glare. Many people assume that darker lenses must automatically be antiglare, but that’s not the case.

Likewise, darker lenses don’t necessarily offer great UV protection, either. This is an especially dangerous misconception, because darker lenses will cause your pupils to dilate, so they can take in more light.

Unfortunately, if your lenses can’t block glare, you’re more vulnerable to eye strain. Even worse, if your lenses don’t block UV rays, your eyes will take in more of them, which could lead to anything from sunburned eyes tomacular degeneration to intraocular cancer.

So, play it safe, and entrust your eyes to polarized sunglasses with UV protection.

What if My Sunglasses Aren't Polarized?

Well, then I hope you like glare.

In all seriousness, sometimes, glare isn’t such a bad thing. If you absolutely need to read digital readouts while in direct sunlight (e.g. if you’re racing in a vehicle or flying a plane), then cutting out glare could make this difficult and dangerous. Similarly, skiers often put up with glare because it can make it easier to tell the difference between snow and ice.

For everyone else, glare is always bad. So, if you don’t have a pair of polarized sunglasses, get one.

Personally, I’d recommend Runners Sunglasses.

Is that because I own the company?


But I started it specifically so I could make polarized sunglasses with UV400 protection – the highest possible – that are affordable, fashionable, and functional.

If you live an active lifestyle and like to look good doing it, you’ll love our shades.

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