Flight Haneda Airport departs from Tokyo Haneda Airport at 17:05 and arrives at Singapore Changi Airport at 23:05.
The flighttime is about 7h 00m. The distance travelled ("as the bird flies"): 4314 Km. So the average speed is roughly 616 Km.
There is an 1 hour time difference between Tokyo and Singapore
The best day to arrive at Tokyo is Monday and it would be best to avoid Saturday, as prices are on average 158.71% higher than on Monday. (Average prices, based on 404783 datapoints.)
We have a lot more statistics for flights SQ 633 and between Tokyo and Singapore.