There are
1,838 mi
from St Charles, MO to Seal Beach, CA
That's the driving distance. It would take 1 day 8 hours to go from St Charles, Missouri to Seal Beach, California.
The flight distance (direct flight from St Charles, MO to Seal Beach, CA) is 1,569.84 mi.
1,838 mi = 2,958.03 kms