my notifications have been changing between 14 and 19k for a a while now despite the fact that i never open them, is there a cap?

Notifications only go back a month, but there's apparently no cap on how many unchecked notifications you can have at once.

I'd recommend either checking them more frequently or changing your settings so you no longer receive notifications, since you are loading all the unchecked notifications every single time you load a page. See the posts by @MrMonsh in this thread.

Yeah I don't think there's a cap but the number does start to act kinda weird once you get into the tens of thousands.

Yeah, I've had my notifications in the 15,000 range once before, and can confirm that the number gets a bit funky.

How do you even get to those numbers of notifications in the first place?

The answer is this:

It's a number, between @0 and @2 woweeW

@Half ?