Just a quick thought I was having... There’s a point at which squinting starts to feel like it's a normal thing to do.
I used to think all sunglasses were basically the same. Some were dark, some were light, and that's all I needed to know. I bought them based on how they looked in the mirror or how they made me feel catching my reflection in a storefront window. If I put them on and things got dimmer, I assumed they were working.
That was before I learned about VLT.
VLT Sunglasses Meaning — What Nobody Told Me
Visible Light Transmission (VLT) sounds like one of those overly technical terms reserved for optical engineers or ski goggle manuals. But once I understood what VLT actually meant, it completely changed how I looked at sunglasses — and how I designed them.
Put simply, VLT is the percentage of visible light that passes through the lenses of your sunglasses and reaches your eyes. It's usually expressed as a number between 0% and 100%. The lower the number, the darker the lens. The higher the number, the more light gets through.
But here’s where it gets interesting: the “best light transmission for sunglasses” isn’t the same for everyone — or every situation. I’ll come back to that.
Why VLT Isn’t Just a Number — It’s a Decision
In a world obsessed with binary choices — dark or light, mirrored or matte — VLT invites nuance. A lens with 10% VLT blocks 90% of light, making it ideal for bright midday sun or high-glare environments. These are your classic low VLT sunglasses — the ones that make even the harshest North Carolina afternoons bearable.
But crank that up to 35%, and you're entering the territory of high VLT sunglasses. These let in more light, making them better for overcast days, early morning hikes, or driving through shaded terrain. They sharpen contrast, preserve depth perception, and avoid that feeling of being trapped behind tinted windows.
Low light transmission sunglasses serve a purpose, but they’re not always the right tool.
And that’s the crux of it: VLT isn’t about more or less — it’s about appropriate.
What the Best Light Transmission for Sunglasses Actually Depends On
When someone asks me what the “best” VLT percentage is, I can’t answer without first asking: “Best for what?”
- Everyday Wear: 8–20% VLT tends to hit the sweet spot. Dark enough for comfort, light enough for visibility.
- Mountain or Snow Environments: Go darker. 5–8% VLT helps combat glare from reflective surfaces.
- Overcast, Foggy, or Dense Forest Trails: 25–40% VLT improves clarity without dimming your world into a blur.
- Indoor/Prescription Lenses: 50% and up — these aren’t truly “sunglasses” in the traditional sense but are useful for blue light or low-level glare.
Knowing the light transmission percentage in sunglasses you’re wearing gives you agency — you’re not just reacting to brightness, you’re preparing for it. To see our VLT info, head to our Lens Information page.
How I Use This Knowledge Now
The deeper I went into understanding light transmission sunglasses, the more obvious it became that most brands never talk about it. It’s not sexy. It doesn’t sell frames the way “polarized” does. But it matters — especially when you’ve built your business around solving real-world problems for people with bigger heads, unique faces, and a dozen previous disappointments from sunglasses that didn’t deliver.
I don’t just design based on what looks cool anymore. I test lens tints on trails, parking lots, water, snow, and yes — my daily dog walk under Charlotte’s relentless sun. I think about use case first, and VLT is always part of the formula. Just in case you are interested, my go-to lens is our brown lens that comes with our tortoiseshell frames — VLT 12.99%.
Why Most People Have It Backwards
I’ve noticed that people often buy sunglasses for how they look under fluorescent lights indoors — then take them outside and realize they either can’t see or they’re not protected enough. It’s backward.
In the same way that you wouldn’t buy hiking boots based on how they look on a carpeted shoe store floor, you shouldn’t choose sunglasses without thinking about what kind of light they’ll face.
And just like training your body or your mind, sunglasses aren’t just about removing discomfort — they’re about optimizing experience. Too little light and you’re dulled. Too much and you’re overwhelmed. Find the balance, and your environment feels like it clicks into focus.
VLT and Human Psychology — A Thought Worth Considering
Here’s something I’ve come to believe: the reason VLT resonates so much with me now is because it mirrors the way I try to live.
Let too much noise in — you’re scattered. Let too little in — you’re in the dark.
We spend so much time trying to filter our digital and mental input that it makes perfect sense we should be thoughtful about how we filter literal light. VLT, in that sense, is a kind of boundary setting for the eyes.
Final Thoughts — What I Wish I Knew Earlier
If you’ve never looked into the VLT of your sunglasses, that’s not your fault. It’s rarely printed on packaging, and most salespeople don’t even know what it means. But the truth is, it’s one of the most important specs you can understand — especially if you’re chasing performance, comfort, or just want to stop wasting money on frames that look good but fail you in the real world.
Next time you shop for sunglasses, don’t ask how they look under store lights. Ask what their light transmission percentage is. Ask where they perform best. Ask what kind of VLT range suits your lifestyle. And if it just so happens that you have a large head — well, we are going to be music to your eyes. You should check out our sunglasses for big heads.
It might not feel like a big deal — until you finally get it right.
Then you’ll wonder how you ever lived without it.