Flight Taoyuan International Airport departs from Taipei Taoyuan International Airport at 07:25 and arrives at Chiang Mai Chiang Mai International Airport at 10:25.
The flighttime is about 4h 00m. The distance travelled ("as the bird flies"): 2485 Km. So the average speed is roughly 621 Km.
There is an 1 hour time difference between Taipei and Chiang Mai