Partially. Standard window glass blocks most UVB and nearly all UVC—the wavelengths that cause sunburn. But it only blocks about a quarter of UVA, so roughly three-quarters still gets through. That's why you rarely burn indoors but can still tan or accumulate skin damage sitting by a sunny window.

How different glass types compare

Regular soda-lime glass (most home windows): blocks ~97% of UVB, ~25% of UVA.

Tempered glass (car side windows): similar UVB blocking, blocks 60–71% of UVA.

Laminated glass (car windshields, some safety glass): the plastic PVB layer between the panes does the heavy lifting—up to ~99% of both UVA and UVB.

Low-E coated glass: typically blocks 85–95% of UV overall. Tinted or colored glass (especially amber/brown) blocks more than clear. That's why light-sensitive products come in brown bottles.

Can you get skin damage through glass?

Yes, from UVA. You probably won't sunburn behind a window, but prolonged exposure can contribute to aging and skin cancer risk over time. People who sit near windows for hours—office workers, drivers—sometimes develop uneven tanning or damage on the exposed side.

UVA also fades furniture, artwork, and fabrics. Regular glass won't stop that.

Car windows are uneven

Windshields (laminated) block 94–98% of UVA. Side and rear windows (tempered) only block 60–71%. Drivers often get more sun damage on the window side of their face—that's not a coincidence.

If you want better blocking

UV-blocking window film, Low-E replacement windows, or heavy curtains can cut UVA dramatically—films often claim up to 99% blocking. For existing windows, film is usually the cheapest upgrade.