Miles between Thornton, CO and Duncan, OK

There are
669 mi
from Thornton, CO to Duncan, OK

That's the driving distance. It would take 12 hours 44 mins to go from Thornton, Colorado to Duncan, Oklahoma.

The flight distance (direct flight from Thornton, CO to Duncan, OK) is 534.93 mi.

669 mi = 1,076.31 kms