Flight Kansai International Airport departs from Osaka Kansai International Airport at 14:10 and arrives at Seoul Incheon International Airport at 16:20.
The flighttime is about 2h 10m. The distance travelled ("as the bird flies"): 1002 Km. So the average speed is roughly 462 Km.
The best day to arrive at Osaka is Monday and it would be best to avoid Thursday, as prices are on average 103.58% higher than on Monday. (Average prices, based on 6324182 datapoints.)
We have a lot more statistics for flights KE 728 and between Osaka and Seoul.