There are
2,180 mi
from Keansburg, NJ to Great Falls, MT
That's the driving distance. It would take 1 day 15 hours to go from Keansburg, New Jersey to Great Falls, Montana.
The flight distance (direct flight from Keansburg, NJ to Great Falls, MT) is 1,891.91 mi.
2,180 mi = 3,509.00 kms