How does gaining rift exp work?

Sletitrocks

Is it the same as normal leveling exp? Because I'm pretty sure it's not. At least it didn't seem like that. Do you have to do well or is it also just time played? And of course, is there a best way to farm it?

Peanits

It is the same as your player level XP, yes. The vast majority of that XP comes from playtime, with only small bonuses for emblems. The only other notable source of XP comes from daily first match bonuses.

Brawler

800 XP = 1 Rift Fragment. Amount of XP gained depends on the duration of a match. You also get an XP bonus for the first game as a killer and as a survivor. Usually you get around 600 XP per game.