How is XP calculated?

So I've been leveling up my account and got a 3 day xp boost with the free RP. I read on the wiki that the boost would double my xp, but it didn't seem to be having much of an effect. This got my looking around to try to figure out just how xp was calculated as the way the wiki stated (#of minutes x 3 + 25) didn't seem to be accurate. Does anyone know exactly the formula that is used to calculate how much xp you get per match?