It's a fair question.

There's, like...a lot of iPhones now. So how many of them are waterproof? When did phones start becoming waterproof, anyway?

Just to be clear, no iPhone out there is completely waterproof. If you leave a phone in water or some other liquid for long enough, it's gonna die. For that reason, manufacturers tend to use the term "water resistant."

The International Electrotechnic Commission uses ratings to describe a device's durability. This is called a device's IP Code. The IP Code is made up of two numbers. The first number represents a device's protection against solid objects (from 0 to 6, 0 being not protective at all). The second number represents a device's protection against liquids (from 0—9, 0 being not protective at all).

So, if you're wondering which iPhones are water resistant, as well as how resistant they are, have a look below and see if you spot yours and its IP Code according to Apple.

Which iPhones are water resistant?
The short answer? iPhones 7 and later, all the way up through the latest iPhone 13. However, the degree of protection varies amongst the iPhones in this group — and there are many iPhones.

iPhone models and their degree of protection (IP Code)
The iPhone models below are the most water resistant, and carry a rating of IP68 (maximum depth of 6 meters for up to 30 minutes).

iPhone 13
iPhone 13 mini
iPhone 13 Pro
iPhone 13 Pro Max
iPhone 12
iPhone 12 mini
iPhone 12 Pro
iPhone 12 Pro Max
The iPhone models below are slightly less water resistant, and carry a rating of IP68 (maximum depth of 4 meters up to 30 minutes).

iPhone 11 Pro
iPhone 11 Pro Max
The iPhone models below carry a rating of IP68 (maximum depth of 2 meters up to 30 minutes).

iPhone 11
iPhone XS
iPhone XS Max
The iPhone models below carry a rating of IP67 (maximum depth of 1 meter up to 30 minutes).

iPhone SE (2nd generation)
iPhone XR
iPhone X
iPhone 8
iPhone 8 Plus
iPhone 7
iPhone 7 Plus
As Apple Supports notes, a device's protection rating is not permanent. If you submerge your iPhone 13 in water for 20 minutes, it'll may be fairly protected that time. But if you were to keep submerging it in water again and again, it's possible its degree of protection will decrease over time.

Find this list, along with tips on how to keep your iPhone safe from damage (avoid "swimming or bathing with your iPhone," for one) and pointers on what to do if your iPhone gets wet, check out the Apple Support page.