CloneSpy Free Duplicate File CleanUp Tool for Windows

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CloneSpy offers you a complete mechanism for determining which duplicate or same-name files should be removed. It is also possible to leave this decision up to the individual user.

CloneSpy can handle equal files by

deleting redundant files
moving redundant files to a specific folder
exporting a list of all equal files without removing any files
deferring file operations on redundant files to a batch file where you can apply arbitrary file operations