Anti-Twin vs dupeGuru

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.

dupeGuru is a desktop tool for finding duplicate files on Linux, macOS, and Windows. Its Standard, Music, and Picture modes offer different ways to compare files. Filename scans can detect similar names, while Music mode can compare names or selected tags and show music-specific details. Picture mode looks for similar images, including different-sized images when that preference is enabled. Contents scans identify exact matches, first using file sizes to rule out files that cannot match and then comparing contents with MD5 hashes. A recursive contents scan can also locate duplicate folders. Users can filter and sort results, preview files, and delete, move, or copy marked duplicates. Reference folders and duplicate groups are designed to protect reference files and leave at least one item in each group. The documentation recommends checking results before deletion: similar-word matching can cause false positives and slow scans, and picture comparisons can be CPU-intensive. dupeGuru is free, with packages listed for Windows, macOS, Debian, RPM, Arch Linux, and Ubuntu PPA.