Hvar to Dubrovnik?

There is also a faster ferry that leaves from Hvar town almost daily and goes to Korcula (the ferry Steve mentions may leave from Stari Grad on the other side of the island), but does not continue on to Dubrovnik. The only issue is that it arrives in Korcula in the evening and the Ferry or Bus to Dubrovnik does not leave until early morning. That means an overnight stay, or if you want to see Korcula town (I would recommend) it means two nights there. The bus from Korcula is maybe a little faster than the ferry and just as scenic.

Going back to Split may sound like the long way to Dubrovnik, but it's just as fast or faster than the twice weekly ferry. Ferry would more be relaxing and beautiful provided schedule fits your travel days. Otherwise, take the catamaran to Split, walk 5 minutes to the bus station and take a bus to Dubrovnik. Might be wise to buy your bus ticket before departing Split for Hvar. You can time the bus based on catamaran return schedules, and that way you'll be sure to get a seat on a bus at your preferred time.