There are
1,990 mi
from Simi Valley, CA to Rockford, IL
That's the driving distance. It would take 1 day 11 hours to go from Simi Valley, California to Rockford, Illinois.
The flight distance (direct flight from Simi Valley, CA to Rockford, IL) is 1,692.42 mi.
1,990 mi = 1.61 kms