Here’s the thing people get backwards: sunburn and sun damage aren’t the same thing.
The sun sends out two types of UV rays that matter here — UVB and UVA. UVB rays are what cause sunburn. That red, stinging, peeling feeling? That’s UVB doing its thing. UVA rays are quieter — they go deeper into your skin and cause the kind of cell damage that leads to skin cancer, but you won’t feel them working.
Now here’s where car windows come in. All standard glass — in cars, homes, offices — completely blocks UVB rays. So no, you technically cannot get sunburned through a car window. The burn-causing rays don’t make it through.
But UVA? Those pass right through most side windows and sunroofs like they’re not even there.
Your windshield is actually different. It’s made with laminated glass — two layers bonded together — and it blocks most of both UVA and UVB. Side windows and sunroofs, though, are typically made with tempered glass, which doesn’t have that same protection. So the rays coming in from your left while you’re driving? Those are getting to your skin.
This is why some people end up with noticeably more sun damage on the left side of their face and left arm after years of driving. It’s not bad luck. It’s physics.
You won’t feel it happening, which is exactly what makes it easy to ignore. No burn, no pain, no obvious sign. But the damage is still accumulating every time you’re in the sun for a long stretch — a road trip, a daily commute, sitting by a window for hours.
If you want actual protection, wear sunscreen on exposed skin even in the car, or look into UV-blocking window film. Some cars come with UV-treated side windows, but it’s not universal — check what your car actually has if you spend a lot of time driving.