rdfind
rdfind.pauldreik.se
What it is
rdfind is a free command-line utility that finds duplicate files by comparing contents rather than names. It searches supplied directories recursively, including comparisons within or across directories, and can also accept individual files. Matching uses file size, first and last bytes, checksums, and inode or device identity. Supported checksums are MD5, SHA-1, SHA-256, SHA-512, and xxh128, with SHA-1 as the default. By default, rdfind writes a results file without changing files. Options can delete duplicates or replace them with symbolic or hard links, while a dry run previews an enabled action. Filters can ignore empty files or set minimum and maximum sizes. It runs on Linux, macOS, and Windows; Linux packages include apt and dnf examples, Mac installation can use MacPorts, and Windows users may use Cygwin. The manual warns about changing directories during a run, symlink attacks when deleting or linking, and unsupported ownership or permissions handling.
Spec sheet
- Purpose
- rdfind finds duplicate files by comparing their contents rather than their names, and can help compress backup directories.Read 9 Oct 2026 · rdfind.pauldreik.se
- Support
- The site directs users to GitHub issues for bug reports and feature requests and invites suggestions and comments.Read 9 Oct 2026 · rdfind.pauldreik.se
- Founded
- 2006Read 28 Sep 2026 · rdfind.pauldreik.se
- Checksum options
- It supports MD5, SHA-1, SHA-256, SHA-512, and xxh128 checksums; SHA-1 is the default.Read 9 Oct 2026 · rdfind.pauldreik.se
- Duplicate handling
- By default, rdfind writes a results file and takes no action; options can delete duplicates or replace them with symbolic or hard links.Read 9 Oct 2026 · rdfind.pauldreik.se
- File filtering
- Options can ignore empty files and set minimum and maximum file sizes.Read 9 Oct 2026 · rdfind.pauldreik.se
- Linux installation
- The official site says most Linux distributions have packages and gives apt and dnf installation examples.Read 9 Oct 2026 · rdfind.pauldreik.se
- Maintainer
- The site identifies Paul Dreik as rdfind's author.Read 9 Oct 2026 · rdfind.pauldreik.se
- Other platforms
- The official site says Mac users can install through MacPorts and Windows users may use Cygwin.Read 9 Oct 2026 · rdfind.pauldreik.se
- Ownership limitation
- The manual says rdfind does not handle file ownership and permissions and is not recommended across directories with several owners.Read 9 Oct 2026 · rdfind.pauldreik.se
- Recursive search
- It finds duplicates within or across directories and searches directories recursively.Read 9 Oct 2026 · rdfind.pauldreik.se
- Safe preview
- Its dry-run option prints what an enabled action would do instead of carrying it out.Read 9 Oct 2026 · rdfind.pauldreik.se
- Security guidance
- The manual warns that changing directories during a run can make rdfind brittle and that deleting or linking can expose it to symlink attacks.Read 9 Oct 2026 · rdfind.pauldreik.se
Plans and prices
rdfind Free GPLv2 or later Read 9 Oct 2026 · rdfind.pauldreik.se
Strong points and limits
Strong points
- Free and cross-platform
- Recursive searches across directories
- Several checksum choices
- Dry run previews enabled actions
- Can delete or link selected duplicates
Limits
- Command-line operation only
- No recycle-bin or Trash route
- Does not handle ownership or permissions
- Deleting or linking can expose symlink risks
Who it suits
People comfortable supplying scan targets at the command line who need duplicate detection across Linux, macOS, or Windows directories. It suits users who want previewable, selectable cleanup actions.
Verdict
rdfind offers content-based duplicate detection with configurable checksums, filters, and cautious action controls. Its command-line design and ownership limitations matter when planning cleanup across shared or permission-sensitive directories.
Where Specifiction places it
- Duplicate File Finders#23 of 387.3
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