How long do you have to know someone before you tell a dirty joke?
First things first, if you have a good dirty joke to share don't hold out on us.
Depending on what level of friendship your aiming for, it can take between 50-340 hours to become friends with someone, according to a recent study.
If you'd rather not take that much time here's a few pointers that have always worked for me. Though it's worth noting that my humor is derived very much in the moment and plays off my current conversation/scenario.
I usually give them at least 5mins before making an inappropriate comment, if that's well received I'll go ahead with the dirty joke if it's not well received I go in with a really dirty joke.
The type of discourse I engage in with someone varies person to person. I'll only engage in different types of humor if I can tell they are comfortable. I try to be considerate until I'm sure the other party is comfortable, then I tend to enjoy exchanging stupid insults. My closest friends and I enjoying the insult game...lol.
Usually ten minutes, then the friendship ends.
This is why I'm a hermit.