Anti-Twin, a sophisticated Duplicate File Finder for Windows

Martin Brinkmann
Jun 11, 2012
Updated • Sep 17, 2018
Software, Windows software

Depending on how you store, download and transfer files, duplicate files may make up a portion of the used disk space on the computer. While that may be a problem at all if there is plenty of free disk space available on a device, it may become one if disk space is not available in abundance.

A duplicate file finder like Anti-Twin may help you find and delete duplicate files on the device to free up disk space and improve manageability.

Find duplicate files with Anti-Twin for Windows

duplicate file finder

The duplicate file finder is available as a portable version and version that needs to be installed, and you can pick either one as they provide you with the same feature set.

Once you launch Anti-Twin you can start configuring search parameters as this happens directly in the main interface.

You do need to pick at least one directory on a connected hard drive that you want to scan for duplicate files. If you want, you can add a second folder as well; useful if you want to find duplicates in two different paths on the system.

The program includes subfolders automatically in the scan; you can disable the option if you prefer to only scan files in root folders as it may speed up the scan among other things.

A click on file filter displays additional filtering options, in particular to only include files that match a minimum or maximum file size, or files with specific extensions.

files by extensions

Anti-Twin compares all files matching the filters using a byte by byte analysis to make sure that it only catches identical files. You can change the comparison method on the start screen as well. For images, you can switch to a pixel comparison option, and for all files to a comparison by name instead.  If you select the latter, you can furthermore only include files that have identical file sizes, and files that only differ in the file extension.

Name-based filters are useful only if you keep the subfolder option enabled or select a second root folder for the scan.

It is last but not least possible to change the threshold for a match from 100% to a lower value. A click on the search button runs the scan using the selected search parameters.

The duplicate file scan may take some time depending on the number of files in folders, the comparison method and the performance of the PC. A few tests revealed however that operations are completed rather quickly even when thousands of files need to be compared.

The results listing displays all matches in the interface; each match is listed with its file name and path, date of creation, and the size it occupies on the hard drive. Here you can mark individual duplicates for deletion, or let the program make the selection for you.

duplicate file listing

You may modify the parameters for the auto selection of duplicate files:

  • Prefer files that have an older or newer creation date
  • Prefer files that are smaller or larger than other duplicates
  • Prefer files that are closer or farther away from the root directory
  • Prefer files names that indicate a copy

Hover your mouse over image duplicates to see  a preview of the image in a small popup window which can be useful for comparison reasons.

Closing Words

Anti-Twin is a sophisticated but still easy to use duplicate file finder for the Windows operating system. It offers different comparison methods, automatic weighting and file filtering, as well as support for a dozen or so different interface languages.  The program is compatible with all recent 32-bit and 64-bit editions of the Windows operating system. According to the author, it will also run on Linux or Mac if Wine is used.

If there is one thing to criticize it is the lack of updates. The latest program version has been released in Max 2010, and while there are not any issues yet with the program, it appears abandoned. The program runs fine on all current versions (and not so current versions) of Windows.

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  1. markbun said on June 27, 2013 at 11:37 am

    I’m using an alternative tool “DuplicateFilesDeleter” a great fix for finding and removing duplicates.

  2. Andy19738 said on August 23, 2012 at 5:16 pm
  3. Andy19738 said on August 23, 2012 at 5:13 pm
  4. Roman ShaRP said on June 16, 2012 at 3:30 pm

    I think I don’t see in this program any advantages over CloneSpy I’m using for years for duplicates search and deletion.

    CloneSpy is somewhat more sophisticated, though.

  5. Shawn said on June 13, 2012 at 5:49 am

    Just wanted to let you know this program is great but there is one major issue… If your ram size is not large enough it will crash at 300k+ files on verification. I suggest to all that use it to use the file size to split the research into 2 parts and by doing so it reduces the load on the system.

    And yes even your grandmother could use this tool theres nothing to it ;-)

    Thanks for a great find.. with 10 tb+ of junk i’m glad programmers / gurus make theses awsome tools..

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