Flight Narita International Airport departs from Tokyo Narita International Airport at 20:05 and arrives at Taipei Taoyuan International Airport at 22:45.
The flighttime is about 3h 40m. The distance travelled ("as the bird flies"): 2260 Km. So the average speed is roughly 616 Km.
There is an 1 hour time difference between Tokyo and Taipei
The best day to arrive at Tokyo is Sunday and it would be best to avoid Wednesday, as prices are on average 528.97% higher than on Sunday. (Average prices, based on 2119121 datapoints.)
We have a lot more statistics for flights CI 109 and between Tokyo and Taipei.