Similarity is a pretty awesome app for anyone who doesn’t keep their music library organized. I don’t have a very large music library (just a few hundred songs), but I know people who have tens of thousands of songs. Once it starts getting that big I could see some duplicate songs sneaking in there… maybe because you’ve got two albums by the same artist that overlap a bit, which is very much possible once you start diving into “best of” albums. Similarity can try to take care of that for you.

Once you run the app you can point it to the location that needs to be scanned. It will start going through the music looking at the actual content of the song as well as the tags used. It can recognize duplicates even if the durations are off from each other, or if they are different formats/filetypes.

Here’s a full breakdown of the features:

  • Three powerful comparing algorithms (content based, tags based and experimental).
  • Support lossy formats: MP3, MP2, OGG, WMA, ASF.
  • Support lossless formats: FLAC, APE(Monkey Audio), WV(WavePack), MPC(MusePack), WMA.
  • Support ID3v1, ID3v2, APEv2, WMA, Vorbis tags.
  • Find files with same sound content (not byte to byte comparison, using sound analyzing).
  • Tag editor (support MP3,WMA).
  • Tag/file renaming tool.
  • Very fast sound content scanning.
  • Support Windows 7 Libraries.
  • Works with removable media devices like USB, etc.
  • Search local PC and over network.
  • Find duplicate from a selected set of folders.
  • Show files tags and properties.
  • Results can be exported to playlist.

Given the small size of my music library I didn’t really have any duplicates, but I’d be interested to hear how this performs on some of your libraries.

Similarity Homepage (Windows only; Freeware)