Please be aware that Tokyo and Bangkok has multiple airports and that these results are for all airports serving the city.
The best month to fly between Tokyo and Bangkok is June and the most expensive month to fly is March. (Average prices, based on 270 datapoints.)
The best day to arrive at Tokyo is Tuesday and it would be best to avoid Sunday, as prices are on average 85.21% higher than on Tuesday. (Average prices, based on 679 datapoints.)
The cheapest airline flying from Tokyo to Bangkok is Thai Airways. They are 70% cheaper than All Nippon Airways. (Average prices, based on 280 datapoints.)
The best time to fly is at around 17. (Average prices, based on 387 datapoints.)