Flight Narita International Airport departs from Tokyo Narita International Airport at 19:20 and arrives at Hong Kong Hong Kong International Airport at 23:15.
The flighttime is about 4h 55m. The distance travelled ("as the bird flies"): 3064 Km. So the average speed is roughly 623 Km.
There is an 1 hour time difference between Tokyo and Hong Kong
The best day to arrive at Tokyo is Sunday and it would be best to avoid Monday, as prices are on average 79.13% higher than on Sunday. (Average prices, based on 14372744 datapoints.)
We have a lot more statistics for flights UO 647 and between Tokyo and Hong Kong.
THB