Why duplicates appear
- A song was downloaded twice, and the second file became "Song (1).mp3".
- The same song exists as an MP3 and as a FLAC or M4A.
- A folder was copied to a second drive or a second place and never cleaned up.
- Two rips of the same CD, or two downloads of the same track, came from different sources.
Each copy takes space and clutters your search results. In the 60,902-song library we built the tools on, 10,391 songs had at least one extra copy. Together the extra copies came to 18,913 files and about 169 GB.
The two kinds of duplicate
Exact copies have the same size and the same sound, and they may sit in one folder or in different folders, and the names can differ, but the file is the same file.
The same song in different files is a different problem. An MP3 and a FLAC, two rips, or two bitrates of one song have different contents, so a simple comparison of the files will not match them. What matches is the artist and title saved inside each file, and the play time.
How Repair My Music will find them
The Duplicates tool will do these steps for a whole library.
- Exact copies. Files with the same size and the same sound are grouped together. Finding exact copies, empty files, and odd file types took 25 seconds on 60,525 files in our library.
- The same song in different files. Files with the same artist and title saved inside them, and a play time that agrees, are grouped together as the same song.
- The best copy is ranked first. In each group, one copy is suggested as the one to keep, with a note under each copy saying why it is better or worse.
- You choose. Nothing is removed until you tick it. One copy of every song always stays, even if you tick every copy in a group.
- Removals go to the Windows Recycle Bin, so you can restore any file from there.
How it decides which copy to keep
It looks first at whether the song plays cleanly, then at the file type and bitrate, and a lossless file ranks above a lossy one, and a higher bitrate ranks above a lower one. After that it prefers a file with an artist and title saved inside it, a name that does not look like a second copy, such as "Song (1)" or "Song - Copy", a longer play time and a tidier folder. The suggestion is only a suggestion, and you can change it.
Two traps it is built around
The same title is not always the same song. A radio edit, an extended mix, and a live version can all share an artist and a title, and the play time has to agree before two files are grouped, and every group is shown to you before anything is removed.
Never remove every copy. That is why one copy of every song always stays.
How Duplicates compares with dupeGuru
dupeGuru is a free, open source duplicate finder with a music mode, and it matches songs by file name, tags, or file contents.
Duplicates is built around music libraries. It finds exact copies by size and sound, and it groups the same song across MP3, MP2, M4A, WMA, and WAV files by artist, title, and play time. Each group ranks the copies and says why, and one copy of every song always stays, even if you tick them all.
Facts about the other tools were checked on 12 November 2026. Sources: dupeGuru, MajorGeeks; dupeGuru Music Edition, AlternativeTo; dupeGuru Music Edition settings, I Love Free Software.
What it will not do
- It will not pair up files whose saved artist and title differ or are missing. Finding duplicates by sound is planned for later.
- It does not clean the duplicate lists inside iTunes, Apple Music or Spotify, and it works on music files in folders.
- It runs on Windows first.
Close your DJ software before you remove anything. Read about Duplicates, or see what we found in a real 60,902-song library.