There are
1,290 mi
from St Peters, MO to Layton, UT
That's the driving distance. It would take 22 hours 30 mins to go from St Peters, Missouri to Layton, Utah.
The flight distance (direct flight from St Peters, MO to Layton, UT) is 1,140.19 mi.
1,290 mi = 2,076.40 kms