Flight Narita International Airport departs from Tokyo Narita International Airport at 09:25 and arrives at Taipei Taoyuan International Airport at 12:05.
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 Saturday and it would be best to avoid Friday, as prices are on average 271.87% higher than on Saturday. (Average prices, based on 2131839 datapoints.)
We have a lot more statistics for flights JL 5045 and between Tokyo and Taipei.