Flight Incheon International Airport departs from Seoul Incheon International Airport at 23:15 and arrives at Singapore Changi Airport at 04:55.
The flighttime is about 6h 40m. The distance travelled ("as the bird flies"): 2923 Km. So the average speed is roughly 438 Km.
There is an 1 hour time difference between Seoul and Singapore
The best day to arrive at Seoul is Thursday and it would be best to avoid Wednesday, as prices are on average 134.29% higher than on Thursday. (Average prices, based on 852590 datapoints.)
We have a lot more statistics for flights OZ 6783 and between Seoul and Singapore.
