Please be aware that Istanbul has multiple airports and that these results are for all airports serving the city.
The best month to fly between Istanbul and Amsterdam is June and the most expensive month to fly is August. (Average prices, based on 1001 datapoints.)
The best day to arrive at Istanbul is Monday and it would be best to avoid Tuesday, as prices are on average 129.72% higher than on Monday. (Average prices, based on 496 datapoints.)
The best time to fly is at around 12. (Average prices, based on 1822 datapoints.)