Flight Kansai International Airport departs from Osaka Kansai International Airport at 17:25 and arrives at Singapore Changi Airport at 23:05.
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 Friday and it would be best to avoid Tuesday, as prices are on average 962.13% higher than on Friday. (Average prices, based on 144319 datapoints.)
We have a lot more statistics for flights SQ 621 and between Osaka and Singapore.