7-Zip is a free (open source) file archiver with a high compression ratio (when using its own compression format).
Features: High compression ratio in 7z format with LZMA compression; It supports packing / unpacking of 7z, ZIP, GZIP, BZIP2 and TAR; Unpacking only: ARJ, CAB, CHM, CPIO, DEB, DMG, HFS, ISO, LZH, LZMA, MSI, NSIS, RAR, RPM, UDF, WIM, XAR and Z;
Strong AES-256 encryption in 7z and ZIP formats; Self-extracting capability for 7z format; Integration with Windows Shell; Localizations for 74 languages; and more.
Note that 7-Zip may face problems when extracting ACE archives. If you work with this type often, try instead PeaZip or IZarc.

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