How can you tell if car glass is tempered or laminated?
Reviewed by the Skyview Auto Glass technical team — NWRD-, ASE- and DINITROL-trained technicians · Updated November 2026
Quick answer
Check the corner stamp, the edge of the pane, and the view through polarized sunglasses. Tempered glass carries a maker’s mark in a corner and shows no layered edge. Laminated glass shows a sandwich line where two glass layers meet the plastic interlayer, and it often looks slightly different through polarized lenses. The windshield is always laminated.
How to tell if glass is tempered
- Look for a stamp in the corner — tempered glass carries a maker’s mark or the letters AS or TEMPERED.
- Check the edge of the pane, if it is exposed. Laminated glass shows a visible sandwich line; tempered glass does not.
- Wear polarized sunglasses and look for a stressed pattern in the glass, which appears under polarized light on tempered panes.
- Remember the windshield is always laminated, so any tempered glass is on the sides or rear.
Tempered vs laminated at a glance
Use these signs to tell the two apart without breaking anything.
| Sign | Tempered glass | Laminated glass |
|---|---|---|
| Corner stamp | Maker’s mark, AS, or TEMPERED | LAMINATED or LAM |
| Edge (if exposed) | Solid, no layers | Sandwich line visible |
| Through polarized lenses | Stress pattern may show | Looks more uniform |
| Where it is used | Side and back windows | Windshield, some side glass |
Some newer vehicles use laminated side glass for sound and security, so do not assume every side window is tempered.
Why it matters which glass you have
Laminated side glass holds together when struck, which slows a break-in but also means an escape tool will not break it. Tempered side glass shatters when struck in a corner. Knowing which you have matters in an emergency. See our guide on breaking a car window in an emergency.
More questions about identifying car glass
How can you tell if a car window is laminated?
Look for a LAMINATED stamp in the corner and a sandwich line at the edge where the two glass layers meet the plastic interlayer. The windshield is always laminated; some newer side windows are too.
Do my side windows have laminated glass?
Most side windows are tempered, but some newer vehicles use laminated side glass for sound and security. Check the corner stamp and the edge, or the vehicle owner’s manual, to be sure.
How do you tell if glass is tempered?
Look for a maker’s mark or the word TEMPERED in the corner, and check that the edge shows no sandwich line. Under polarized sunglasses, tempered glass may show a stress pattern.
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