You don't need a swim cap for the beach.

No, unless you’re doing serious lengths in the ocean or protecting a fresh dye job. For a casual beach day, a swim cap is mostly useless.

Swim caps exist for two real reasons: keeping hair out of the way during lap swimming (reducing drag and fogging goggles) and protecting hair from chlorine if you’re in a pool all day. At the beach, saltwater is less damaging, and you’re not exactly worried about drag when you’re body surfing or floating around. They also keep long hair from tangling a bit, but a braid or bun works just as well.

If you’re worried about sunburn on your scalp, a hat or sunblock does a better job. Swim caps don’t block UV well—they’re thin silicone or latex. And they can be a pain to put on when your hands are sandy.

Save the cap for lap swim. Bring a towel and a good hat for the beach.