Split night life isn't much. You probably won't party hard if you're not in the maximum party mood. Split people are layed back and wont rock the dance floor, and they generaly like geting out late. Trying to have a good time before 12:00PM is hard.
The hot spots in Split that you will probably get directed to are:
Vanilla
Hemingway
Hedonist
Imperium
Bačvice
Tropico
ST Riva
F caffe
O'Hara
There are a lot more little cafe bars that get active on summer but these are probably the most visited ones by locals or tourists.
My first pick for a young toursit group wanting to get down is Bacvice beach. It has a a little complex building with lots of little clubs in it. The main ones are Bacvice club (duuuh..) and Tropico club. Bacvice has an open terrace and a coctail bar. Its mostly populated by tourists. Electro, house, regular party stuff by the DJ.Its active every night during the summer. Tropico probably gets more locals.And its closed(although when it opens all the windows, its like in the open.
If you are going out early you should visit the town center and the main Split promenade Riva.
There you will find ST Riva and F caffe that can have the habit of turning the speakers up a little. Coctail bars can be found and a good warm up place.On the down side they are running until 11-12 PM.
If you go to the car ferry you will probably see Imperium. It is a new place in Split so i really don't know how it will be during the summer but you can give it a shot if you are walking to Bacvice.
If you are going further East you will walk by O'Hara. 2 level club that mostly plays Rock and Trash music. Near them is Hedonist.Its more of a classy place to go to,and 95% locals.
The two places you will probably need to take a taxi to is vanila and Hemingway. Vanilla is probably the most active and known nightlife in Split at the moment. It is also active in the summer. A lot of locals there due to the fact that it's not really in walking distance from the center.Also a place where the crowd doesnt sow up until 1AM minimum.
During the rest of the year Hemingwey is more of a young people place. So i really don't know what will they do doring the summer. I had some good times here, but not recently.YOu can give it a visit if you are coming to Vanilla(its probably 300 m from it)
As you can see, most clubs are grouped. You can have fun in the center of the city but it will last until 11-12 PM.Taxi i Split is expensive(at least for locals). It will cost you about 50 kn in one direction minimum. You won't get cheaper if you bargin with the driver( you will probably get a 200kn price if you ask, so be sure he turns on the taximeter)
I made a little map for you with all the clubs in it so you know what im talking about:
You can check some photos frome these places at http://www.nightlife.hr/galerije/.
If you want to know about the beaches i made a small map and review of all the beches in Split:
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