Flight Taoyuan International Airport departs from Taipei Taoyuan International Airport at 00:15 and arrives at Singapore Changi Airport at 04:55.
The flighttime is about 4h 40m. The distance travelled ("as the bird flies"): 2134 Km. So the average speed is roughly 457 Km.
The best day to arrive at Taipei is Monday and it would be best to avoid Friday, as prices are on average 181.85% higher than on Monday. (Average prices, based on 510903 datapoints.)
We have a lot more statistics for flights TR 875 and between Taipei and Singapore.