Flight Soekarno–Hatta International Airport departs from Jakarta Soekarno–Hatta International Airport at 21:45 and arrives at Tokyo Narita International Airport at 06:50.
The flighttime is about 7h 05m. The distance travelled ("as the bird flies"): 4356 Km. So the average speed is roughly 615 Km.
There is an 2 hour time difference between Jakarta and Tokyo
The best day to arrive at Jakarta is Monday and it would be best to avoid Friday, as prices are on average 52.58% higher than on Monday. (Average prices, based on 21961042 datapoints.)
We have a lot more statistics for flights NH 856 and between Jakarta and Tokyo.