Flight Narita International Airport departs from Tokyo Narita International Airport at 12:00 and arrives at Bangkok Suvarnabhumi Airport at 16:30.
The flighttime is about 6h 30m. The distance travelled ("as the bird flies"): 4511 Km. So the average speed is roughly 694 Km.
There is an 2 hour time difference between Tokyo and Bangkok
The best day to arrive at Tokyo is Saturday and it would be best to avoid Friday, as prices are on average 2244.75% higher than on Saturday. (Average prices, based on 119513 datapoints.)
We have a lot more statistics for flights NH 5955 and between Tokyo and Bangkok.