Anti-Twin vs jdupes

Anti-Twin searches hard disks and other storage locations for duplicate or similar files. It can compare names, check file contents byte by byte, search for binary similarity, and compare images by their pixels. The image method can find similar pictures even when they have different compression rates or file formats. Search locations include local drives, USB flash disks, memory cards, shared network folders, and a second folder or path. Results can be selected automatically, exported as an Excel file, and sent to the Recycle Bin or deleted.

The program is free for private use and dates to 2003. The download page lists 32-bit and 64-bit Windows, and says it can run through Wine on Linux or Mac and on ReactOS. It can also be installed and started from a USB memory stick. Anti-Twin does not search the Internet or FTP servers, excludes files larger than 2 GB from comparisons, and has no restore function for deleted files. The site says it was maintained until 2012 and still runs on Windows 10 and 11.

jdupes is a free utility for finding and handling exact duplicate files on Linux, macOS, and Windows. It identifies files that are fully identical rather than matching images, sounds, or other formats by similarity. Matching can use file size, hashes, and byte-for-byte comparison, with optional partial-hash matching. The project says it checks matching data after hashing to reduce the chance of false matches from hash collisions. Found duplicates can be reviewed before deletion, deleted without prompting, linked, summarized, or handled through copy-on-write deduplication. On Linux and Unix, the instructions use command-line directory paths; the project also provides a native Windows port, including support for Unicode. Docker use is documented, and standard output can feed shell scripts. A database can retain scan metadata for repeat runs, though the project labels that feature as under development and notes quirks. The README warns that quick matching skips byte-for-byte checks and can classify non-duplicates as duplicates. It also warns that disabling file-change checks creates a security vulnerability, especially when linking or deleting. jdupes is distributed under the MIT License.