Open Source Windows Duplicate File Finders

FDUPES is a lightweight command-line utility that helps users find and optionally delete duplicate files within specified directories by comparing file contents, which can be extremely useful for cleaning up storage clutter or organizing large collections of files. It works by scanning directories and subdirectories, identifying sets of files with identical content through size and hash comparisons, and then listing them together so users can examine duplicates. Once duplicates are identified, the tool offers interactive deletion options where users can choose which copy to keep and which to remove, or apply flags to automate deletion while preserving a single instance. Because it operates directly on file content rather than just filenames, fdupes can accurately detect true copies and guide cleaning operations in data cleanup or migration tasks. It’s a simple, efficient, and widely used utility on Unix-like systems, appreciated by administrators, developers, and power users.

HashCatalog is a program that can find duplicate files in one or more folders, or between 2 lists of one or more folders. HashCatalog can also create an xml database file containing a listing of files with hashes.