Worked for me

Had a situation where almost 20,000 songs were duplicated (all legal, I swear - my wife and I were huge CD collectors!) and there was no easy way to go through and delete them. Facing down the prospect of restoring the library from Time Machine, it occurred to me that I might find a duplicate killer here on the App Store. I don’t know anything about this sort of software, but this is the one I settled on. And… it worked like a charm! Because of the size of my library it took a little bit to run, but it got the job done. Worth every penny!

Kris and Steph Wright about Song deDuper