Please be aware that Seoul and Tokyo has multiple airports and that these results are for all airports serving the city.
The best month to fly between Seoul and Tokyo is August and the most expensive month to fly is September. (Average prices, based on 451 datapoints.)
The best day to arrive at Seoul is Wednesday and it would be best to avoid Tuesday, as prices are on average 46.61% higher than on Wednesday. (Average prices, based on 201 datapoints.)
The cheapest airline flying from Seoul to Tokyo is EastarJet. They are 57% cheaper than All Nippon Airways. (Average prices, based on 485 datapoints.)
The best time to fly is at around 8. (Average prices, based on 947 datapoints.)
