Flight Changi Airport departs from Singapore Changi Airport at 06:15 and arrives at Tokyo Narita International Airport at 14:30.
The flighttime is about 7h 15m. The distance travelled ("as the bird flies"): 4385 Km. So the average speed is roughly 605 Km.
There is an 1 hour time difference between Singapore and Tokyo
The best day to arrive at Singapore is Monday and it would be best to avoid Saturday, as prices are on average 240.91% higher than on Monday. (Average prices, based on 490250 datapoints.)
We have a lot more statistics for flights NQ 802 and between Singapore and Tokyo.