In time: with enough time to spare.. before the last moment On time: at the planned time.. neither late nor early I reached the station in time, just to see the engine turning on. I reached the station on time, packed my food from Comesum and then boarded the train.

"on time" = at the right time "in time" = before it was too late I got to work on time this morning. I start work at 9:00 and I arrived at 9:00. I got on the train in time, there's still 10 minutes left before it leaves. Another one: just in time = just before it was too late; almost too late It's okay, I ran the whole way and got on the train JUST in time, it leaves in one minute! (just in time = almost too late)

To add to the other answers, "in time" can also mean "eventually." example: In time, she will come to accept it.