How long in real time does the average dream take up?

Can't give you an exact time because everyone is different. But a dream can last all night or start whenever you get into a deep sleep. So it depends. That is all i can tell you. I would measure it by seeing the time you fall asleep and the time you wake up because most dreams end when u wake up but pretty much i dream can last as long as you're sleeping ( sometimes you have to be in a deep sleep). Hope that answers your question!