Flight Kualanamu International Airport departs from Medan Kualanamu International Airport at 10:30 and arrives at Jakarta Soekarno–Hatta International Airport at 12:45.
The flighttime is about 2h 15m. The distance travelled ("as the bird flies"): 895 Km. So the average speed is roughly 398 Km.
The best month to arrive at Medan is September and the most expensive month to fly is March. (Average prices, based on 346 datapoints.)
We have a lot more statistics for flights IW 201 and between Medan and Jakarta.