7-Zip is the only one of our four archiving and compression tools that’s free. It’s open source and offered under the GNU Lesser General Public License. 7-Zip fully supports the following seven compression formats: 7z, bzip2, GZIP, TAR, WIM, XZ, and ZIP. Additionally, 7-Zip can extract an additional 24 formats: ARJ, CAB, CHM, cpio, cramfs, DEB, DMG, FAT, HFS, ISO, LZH, LZMA, MBR, MSI, NSIS, NTFS, RAR, RPM, SquashFS, UDF, VHD, WIM, XAR, and Z.
According to its webpage, 7-Zip’s compression performance for ZIP and GZIP formats is between 2 and 10 percent superior to that of its competition, and our benchmarks support this claim. The app's excellent support for its own 7z compression and archiving format is another strong point. 7z is based on an open architecture with optional 256-bit AES encryption. This format achieved the highest compression rates in our benchmarks. 7-Zip defaults to the Lempel-Ziv-Markov Algorithm (LZMA) for compression with 7z, but it can also be configured to use LZMA2, PPMd, and bzip2. Moreover, it supports WinZip AES encryption, making it possible to create ZIP archives with 256-bit AES encryption.
7-Zip integrates into the Windows Explorer context menus, and it displays archive files as normal folders. This application also has its own file manager, which includes a compression-focused toolbar and drag-and-drop functionality. All Windows versions from 98 to 8 are supported, as are multi-core processors and Hyper-Threading. 7-Zip is available to download in 32-bit or 64-bit versions with a total of 79 languages to choose from.