CAB to TAR.7Z (T7Z) Converter
Convert your cab files to tar.7z online & free
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How to convert CAB to TAR.7Z
Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.
Choose tar.7z or any other format you need as a result (more than 200 formats supported)
Let the file convert and you can download your tar.7z file right afterwards
About formats
CAB (Cabinet) is a compressed archive format developed by Microsoft for efficient software distribution and Windows component packaging. Introduced around 1996, CAB files serve as the container format for Windows Installer packages (.msi), Windows system updates, driver distributions, and ActiveX component downloads. The format supports three compression algorithms — MSZIP (Microsoft's Deflate implementation), Quantum (statistical compression), and LZX (an LZ77 variant with Huffman coding optimized for executable files) — with LZX typically delivering the highest ratios. CAB archives organize files into folders (compression units) where files within the same folder are compressed as a continuous stream for improved ratios, and archives can span multiple volumes for distribution on size-limited media. One advantage is deep Windows ecosystem integration — CAB files are handled natively by Windows without third-party software, used in everything from OS installation media to driver packages and system updates. The LZX compression algorithm provides another strength, achieving particularly strong compression on compiled code and PE executables, which is ideal for the format's primary role in software distribution. Microsoft's makecab tool ships with every Windows installation, and CAB extraction is built into Windows Explorer. The format continues to serve as infrastructure for Windows deployment and update mechanisms across enterprise and consumer environments.
TAR.7Z is a compound archive format that combines the TAR container with 7-Zip's LZMA/LZMA2 compression. The TAR layer bundles multiple files into a single stream preserving Unix metadata (permissions, ownership, symlinks), while the outer 7Z compression applies LZMA or LZMA2 to the entire stream. This combination leverages LZMA's superior compression ratios — typically 30-70% better than gzip — making TAR.7Z one of the most space-efficient archive formats for Unix-style backups and software distribution. The solid-stream approach means compression can exploit redundancy across all archived files rather than compressing each file independently. One advantage is maximum compression density: the TAR.7Z combination often produces the smallest archives among common Unix archive+compression pairings. Broad tool support is another strength — tar and 7-Zip are available on all major platforms, and many modern tar implementations can create and extract TAR.7Z archives directly with the appropriate flag. The format is popular for distributing large source code trees and backup archives where minimizing transfer size justifies the additional compression time.