It intelligently toggles between LZMA , PPMD , and DEFLATE algorithms depending on which produces the smallest file size for a specific file type.

Because this tool re-processes your archives, it is highly recommended to create a backup copy before use.

In benchmark tests, standard 7-Zip archives (at Ultra settings) have been further reduced by the Optimizer. For example, a 11.5 MB archive was reduced to using version 0.03, demonstrating its ability to squeeze extra space out of "already compressed" files.

(often referred to as Ultra7z Optimizer) is a specialised command-line utility designed to further shrink existing 7z, ZIP, or RAR archives by automatically testing and applying the most efficient compression methods. Core Features and Usage

The tool performs a "brute-force" size comparison for each file extension within an archive to ensure maximum space savings.