There are
2,721 mi
from San Clemente, CA to Wilmington, DE
That's the driving distance. It would take 2 days to go from San Clemente, California to Wilmington, Delaware.
The flight distance (direct flight from San Clemente, CA to Wilmington, DE) is 2,352.20 mi.
2,721 mi = 4,379.51 kms