There are
1,823 mi
from Irvine, CA to St Peters, MO
That's the driving distance. It would take 1 day 8 hours to go from Irvine, California to St Peters, Missouri.
The flight distance (direct flight from Irvine, CA to St Peters, MO) is 1,549.54 mi.
1,823 mi = 1.61 kms