Sunscreen definitely expires. Don't risk it.

Yes, sunscreen expires—and the active ingredients degrade over time, making it less effective. The easiest way to tell is to look at the bottle for an expiration date. If there’s no date, write the purchase month on the bottle with a Sharpie and toss it after three years max.

Next, use your senses. If the sunscreen smells off—like old Play-Doh or chemicals that sting your nose—it’s gone bad. Same if the texture is chunky, watery, or separated no matter how much you shake it. And if it ever froze or baked in a hot car, that counts as expired too.

A bad sunburn is not where you save ten bucks.