Anti-Twin vs Czkawka

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.

Czkawka is a free tool for locating duplicate and unnecessary files, empty folders, similar images, and related items. Its tools can find duplicate and empty files, temporary and large files, similar videos, and duplicate music. Scans can target user-selected directories and files, with matches determined by file name, size, full-file hash, or a combination of size and name. Features include file preview, automatic selection, folder exclusions, and moving items to the Recycle Bin or Trash. The project provides graphical and command-line frontends, an Android frontend, a reusable core library, and Python bindings. It says the software uses multithreading and caching to help scans and later rescans, and that it has no internet access and collects no user information or statistics. Czkawka is listed for Android, Linux, macOS, and Windows. GTK 12.0 is the final release for that frontend, and no more GTK binaries are planned. Krokiet prebuilt binaries have no mandatory runtime dependencies, although its similar-videos tool requires ffmpeg at runtime.