You brought your most comfortable noise-cancelling headphones on the plane, but now that you’ve arrived, you want to go kayaking with the sweet sounds of Otis Redding in your ears — without drowning your beloved Bose pair.
Whether you’re swimming, surfing, or just lounging in a splash zone, the key thing to look for in a pair of waterproof headphones is the IP rating. IP stands for international or ingress protection (depending on who you ask), representing how well a product is protected from various solid and liquid intrusions. The first digit of an IP rating is the solid particle protection rating, and the second is for liquids. So a set of headphones with an IP57 rating is equivalent, water-wise, to another pair rated IPX7.
If you want full waterproofing, you need an IPX rating of either 7 or 8. A 7 rating means the headphones can survive being submerged in up to 1 meter of water for up to 30 minutes; an 8 will allow them to go deeper than 1 meter, with the exact depth left up to the manufacturer. Either way, don’t take them scuba diving; it’s bad for the headphones and potentially worse for your ears.