fdupes

Search a single directory

$ fdupes [path/to/directory]

$ fdupes [directory1] [directory2]

$ fdupes [[-r|--recurse]] [path/to/directory]

$ fdupes [path/to/irectory1] [[-R|--recurse:]] [path/to/directory2]

$ fdupes [[-rH|--recurse --hardlinks]] [path/to/directory]

$ fdupes [[-rd|--recurse --delete]] [path/to/directory]

$ fdupes [[-rdN|--recurse --delete --noprompt]] [path/to/directory]

fdupes [options] dir1 [dir2 ...]

-r, --recursive
    Recurse into subdirectories

-s, --size
    Show only first file per size group; skip further duplicate checks

-H, --hardlinks
    Treat identical hardlinks as separate files

-l, --listfiles
    List files without prompting for deletion

-S BYTES, --minsize=BYTES
    Skip files smaller than specified bytes

-X CMD, --exec=CMD
    Execute CMD on each duplicate set ({} for filename)

-o FILE, --output=FILE
    Write output to FILE instead of stdout

-i, --immediate
    Delete duplicates without prompting

-d, --delete
    Interactively prompt before deleting duplicates

-v, --verbose
    Enable verbose progress output

-q, --quiet
    Suppress non-error output

--debug
    Enable debug logging

-1, --oneline
    Display duplicates on single lines

-A, --appledouble
    Skip .AppleDouble files

-f, --stdin
    Read file list from stdin

-I PATTERN, --include=PATTERN
    Include files matching regex PATTERN

--exclude=PATTERN
    Exclude files matching regex PATTERN

-h, --help
    Display help and exit

-V, --version
    Show version information

fdupes is a powerful command-line tool for identifying duplicate files across one or more directories. It efficiently detects duplicates by first comparing file sizes, then computing MD5 signatures for potential matches, and finally performing byte-by-byte comparisons to confirm identical content. This multi-stage approach ensures high accuracy while minimizing unnecessary computations.

Ideal for freeing disk space, managing large media libraries, or cleaning backups, fdupes supports recursive scanning, hard link handling, and interactive deletion prompts. Users can list duplicates, delete them selectively, or execute custom commands on matches. It's lightweight, fast on modern hardware, and handles millions of files effectively.

Output groups duplicates together, showing paths for easy review. Options allow customization like excluding patterns, skipping small files, or quiet mode for scripting. While safe by default (read-only), delete features require caution to avoid data loss.

Delete options (-d, -i) can cause permanent data loss; always backup first. Recursive scans on large filesystems may consume significant time/memory. Not suitable for concurrent use on active directories. Run as non-root to avoid permission issues.

Stage 1: Size filter.
Stage 2: MD5 hash.
Stage 3: Byte comparison for confirmed duplicates.

fdupes -r /home lists duplicates recursively.
fdupes -rd /photos prompts to delete in /photos.

Developed by Jody Bruchon starting in 2007 as an efficient alternative to slower duplicate finders. Actively maintained with performance optimizations; version 2.0+ introduced multithreading. Popular in Linux distros since ~2010; jdupes is a modern fork with enhancements.

jdupes(1), rdfind(1), find(1), md5sum(1)