Flight Changi Airport departs from Singapore Changi Airport at 13:55 and arrives at Tokyo Narita International Airport at 21:50.
The flighttime is about 6h 55m. The distance travelled ("as the bird flies"): 4385 Km. So the average speed is roughly 634 Km.
There is an 1 hour time difference between Singapore and Tokyo
The best day to arrive at Singapore is Saturday and it would be best to avoid Monday, as prices are on average 371.13% higher than on Saturday. (Average prices, based on 506052 datapoints.)
We have a lot more statistics for flights NH 6256 and between Singapore and Tokyo.