Not to be confused with the popular sandwich, VLT is an eyewear thing! In addition to style, color, and function, there are even more ways to customize your glasses or goggles. Ensure your new lenses are tailored just for you by considering the lighting conditions in which you're using your new glasses or goggles. This determines what percentage of VLT, or visible light transmission, you want to allow to pass through the lens. The higher the VLT percentage, the more light is passing through the lens your eye is exposed to. The lower the VLT percentage, the less amount of light is passing through the lens.

So if you really want to, make yourself a BLT and keep reading for everything you need to know about VLT.

VLT: What You Need to Know

1. Lens Tints
2. VLT Categories, Explained
3. VLT Breakdown
3.1. Category 4 (S4)
3.2. Category 3 (S3)
3.3. Category 2 (S2)
3.3. Category 1 (S1)
3.3. Category 0 (S0)
4. Variable VLTs
5. Why VLT Matters
6. Prescription Glasses and Goggles!


Lens Tints

Let's look at which VLT percentages correspond to which type of tint you need. If you want to choose a lens tint specifically for snow goggles, check out How to Choose a Snow Goggle Lens Color | Lens Tech Explained.


VLT Categories, Explained

The different VLT ranges are narrowed down to 'categories' to make it even simpler. The categories (or Cat, for short) go from 4 to 0, with 4 being the darkest and 0 being the lightest. If you're looking at snow goggles, this may be represented with an S (for snow), meaning you can look for S4-S0.


VLT Breakdown

Now that you know what we're on about, we'll get into what to expect out of each VLT category, including what conditions and/or uses they're meant for.

Category 4 (S4)

This VLT range goes from about 3-8%. Lenses with this tint density are for excessively bright conditions and are less common in sunglasses. A tint this dark is unsafe for driving due to it cutting so much light transmission. We need light in order to see, so it can be dangerous to cut too much light transmission when operating vehicles. This VLT range is usually reserved for high-altitude mountaineering or shop welding.

Category 3 (S3)

This VLT range goes from about 10-18%. Tints of this density are typical for everyday sunglasses. The lower end of this VLT range is usually coupled with a mirror coating. They're a great option for driving, activities on the water, or being in the snow. Colors associated with a dark tint are typically grey or copper. This is a good VLT range for sunglasses or goggles used for bright sunny conditions to some clouds.

Category 2 (S2)


This VLT range goes from about 20-43% meant for medium to low-light conditions. This tint is for an average amount of sunlight and for a wide range of activities. If you are not light-sensitive, then this range would also be good for more everyday use.

Category 1 (S1)

This VLT range goes from about 43-80% and is for dusk or other low-light conditions (but not night!) and is especially useful on cloudy days. Colors with light tints are usually yellow, amber, or rose and are chosen for their high color contrast depictions. Good for shooting, cycling, and golf.

Category 0 (S0)

This VLT goes from about 80-100% and means you'll get little to no tint. Even clear lenses can be in the 80% range! Eyewear with this VLT is typically for eyeglasses, fashion, safety, or night activities, including snowboarding and cycling.


Variable VLTs

Are light conditions changing throughout the day? There's a solution to that, and it's called photochromatic lenses. These lenses automatically transition from a clear or light-to-dark tint according to the UV intensity of your environment. Photochromic lenses have a wide range of options that can span from around 15-50% VLT and are versatile enough to work well in just about any condition. The term 'transitions' has become synonymous with photochromic lenses, but it's actually a name brand (and the leading option in terms of quality). Learn more about Transitions lenses here.


Why VLT Matters

You've likely experienced grabbing the wrong pair of glasses when rushing out the door. How would you know? Because the sun just dipped under the water and your lenses are so dark, you're only seeing shadows. Or perhaps you're standing atop a mountain on a luminous day, but your eyes are flooded with light because your lenses aren't tinted enough.

Choosing the right tint for your lenses not only prevents your eyes from being irritated and strained, but it can also be a safety precaution. Stay comfortable and confident with a VLT that is custom to your lifestyle.


Prescription Glasses & Goggles at SportRx

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Need prescription glasses or goggles? Done. When you shop with us, you’ll find video guides and tooltips throughout the build process as you customize the perfect pair. When it comes to goggles, we design and manufacture inserts that are perfect for your goggle! 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 or goggles.

Ditch risky online shopping with the See Better Guarantee. Try your eyewear for 45 days. If you’re not satisfied, send them back. Get a full refund, exchange, or credit towards a better pair. And return shipping? Covered. Get your pair of prescription glasses or goggles at SportRx today!