Flight Keflavík International Airport departs from Reykjavik Keflavík International Airport at 10:30 and arrives at Stockholm Stockholm Arlanda Airport at 15:40.
The flighttime is about 3h 10m. The distance travelled ("as the bird flies"): 4530 Km. So the average speed is roughly 1431 Km.
There is an 2 hour time difference between Reykjavik and Stockholm