There are
1,858 mi
from Carlsbad, CA to St Charles, MO
That's the driving distance. It would take 1 day 8 hours to go from Carlsbad, California to St Charles, Missouri.
The flight distance (direct flight from Carlsbad, CA to St Charles, MO) is 1,544.20 mi.
1,858 mi = 1.61 kms