Flight Narita International Airport departs from Tokyo Narita International Airport at 12:20 and arrives at Singapore Changi Airport at 20:30.The flight has a short stop at Taipei.
The flighttime is about 9h 10m. The distance travelled ("as the bird flies"): 4385 Km. So the average speed is roughly 478 Km.
There is an 1 hour time difference between Tokyo and Singapore