Flight Haneda Airport departs from Tokyo Haneda Airport at 00:25 and arrives at Singapore Changi Airport at 06:55.
The flighttime is about 7h 30m. The distance travelled ("as the bird flies"): 4314 Km. So the average speed is roughly 575 Km.
There is an 1 hour time difference between Tokyo and Singapore
The best day to arrive at Tokyo is Tuesday and it would be best to avoid Wednesday, as prices are on average 334.47% higher than on Tuesday. (Average prices, based on 495472 datapoints.)
We have a lot more statistics for flights NH 843 and between Tokyo and Singapore.