Flight Kansai International Airport departs from Osaka Kansai International Airport at 23:20 and arrives at Singapore Changi Airport at 05:00.
The flighttime is about 6h 40m. The distance travelled ("as the bird flies"): 3803 Km. So the average speed is roughly 570 Km.
There is an 1 hour time difference between Osaka and Singapore
The best day to arrive at Osaka is Saturday and it would be best to avoid Friday, as prices are on average 496.16% higher than on Saturday. (Average prices, based on 255798 datapoints.)
We have a lot more statistics for flights SQ 623 and between Osaka and Singapore.
