There are
1,066 mi
from Thornton, CO to Calexico, CA
That's the driving distance. It would take 18 hours 59 mins to go from Thornton, Colorado to Calexico, California.
The flight distance (direct flight from Thornton, CO to Calexico, CA) is 767.50 mi.
1,066 mi = 1.61 kms