According to Droid-Life, Google has confirmed to the publication that both the Pixel and Pixel XL are IP53 certified. Now before you get too excited, the IP ratings have different meanings, and in the case of IP53, it means that the phone is protected from dust. On the water front, the rating means, “Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect.”
Basically what this means is that you should definitely not take the phone swimming or into the shower with you. It also means that dropping it into the toilet essentially means the end of your phone, unless you’re lucky and somehow there is no water damage. The IP53 rating basically protects your phone from drops of water, like rain, or if you have wet hands, but don’t expect anything more.
If you’d like to learn more about the IP ratings, you can check it out there. In any case with Google headed in a new direction with their Pixel phones, perhaps future models could feature better water-resistance.