There are
1,740 mi
from Sioux City, IA to Foster City, CA
That's the driving distance. It would take 1 day 6 hours to go from Sioux City, Iowa to Foster City, California.
The flight distance (direct flight from Sioux City, IA to Foster City, CA) is 1,404.65 mi.
1,740 mi = 1.61 kms