Please be aware that Bangkok has multiple airports and that these results are for all airports serving the city.
The best month to fly between Bangkok and Krabi is May and the most expensive month to fly is February. (Average prices, based on 9916 datapoints.)
The best day to arrive at Bangkok is Monday and it would be best to avoid Thursday, as prices are on average 42.36% higher than on Monday. (Average prices, based on 2016 datapoints.)
The cheapest airline flying from Bangkok to Krabi is Thai Lion Air. They are 58% cheaper than Thai Airways. (Average prices, based on 9930 datapoints.)