We thought this 24-ounce jug of sunscreen (Supergoop! SPF 30+ Everyday UV lotion, $68; sephora.com
would last us through Labor Day. Then we did the math: Dermatologists recommend at least one ounce (about a full shot glass) of sunscreen to cover your body. And you should reapply it every two hours. So say you're on vacation, spending six hours a day outside—this jug should last you about...eight days.
6 more great sunscreens to try