There are 3 car ferry routes to the Isle of Wight. Red Funnel Operates a car ferry between Southampton and East Cowes while Wightlink operates 2 car ferry routes, one from Lymington to Yarmouth and the other from Portsmouth to Fishbourne.
As the island is relatively small the choice of car ferry route is often down to which port is easiest to reach on the mainland rather than destination on the Isle of Wight.
The links below should help planning your journey, with Interactive route planners, plus links to the 2 car ferry companies.