There are
1,151 mi
from Tallahassee, FL to Johnston, IA
That's the driving distance. It would take 22 hours 7 mins to go from Tallahassee, Florida to Johnston, Iowa.
The flight distance (direct flight from Tallahassee, FL to Johnston, IA) is 936.50 mi.
1,151 mi = 1,852.67 kms