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A program for finding / to locate and optional clean up / purge duplicate files.

It is a console program, to date there is no graphical user interface.


  • Finding duplicate files
    • Bytewise comparison
    • Comparison via MD5 and SHA512 (optional)
  • Clean up / purge of duplicate files:
    • Replace duplicates with links (hard links or soft links)
    • Delete (at which a file is left)
  • Deleting empty files (Size: 0 Bytes)
  • Dry run mode, in which duplum does not touch anything on the filesystem


Version 0.1.1:

  • stable
  • first published version
  • "dry run" mode:
    • logs everything but does not touch the file system!
  • only print BUILD_DATE if set
  • correct flag -show-skip description
  • add flag to display version and exit
  • add flags -max-size and -min-size to skip files based on size


To search for duplicate files between 5 and 100 MiB in all directories below the current:

duplum -dry-run -min-size=5242880 -max-size=104857600 -delete=same .
Note: you can change the dot to a directory (or multiple):
duplum -dry-run -min-size=5242880 -max-size=104857600 -delete=same dir1 dir2 dir3

Note: the flag -dry-run is used in this examples

Copying, licenses & donations

duplum is available without fees for private use.

Albeit donations are welcome.

If you want to use duplum in an environment related to commercial use, military, weapon research and manufacturing and similar;
Please get in contact.


duplum is built for different operating systems and architectures:

  • amd64 for 64-bit architectures,
  • 386 for 32-bit architectures and
  • arm for arm architectures.

SHA512 contains the SHA512 checksum for the archive.

  • check the downloaded archive with shasum:
    shasum -c archive.7z.sha512
  • extract the downloaded archive with 7-zip:
    7z x archive.7z

Old releases can be found in the Archive.