7-Zip is open source software. Most of the source code is under the GNU LGPL license. The unRAR code is under a mixed license: GNU LGPL + unRAR restrictions.
You can use 7-Zip on any computer, including a computer in a commercial organization. You don’t need to register or pay for 7-Zip.
Features:
- High compression ratio in new 7z format with LZMA compression
- Supported formats:
- Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
- Unpacking only: RAR, CAB, ISO, ARJ, LZH, CHM, MSI, WIM, Z, CPIO, RPM, DEB and NSIS
- For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip
- Strong AES-256 encryption in 7z and ZIP formats
- Self-extracting capability for 7z format
- Integration with Windows Shell
- Powerful File Manager
- Powerful command line version
- Plugin for FAR Manager
- Localizations for 69 languages
What’s New:
- The default number of LZMA2 chunks per solid block in 7z archive was increased to 64. It allows to increase the compression speed for big 7z archives, if there is a big number of CPU cores and threads.
- The speed of PPMd compressing/decompressing was increased for 7z/ZIP/RAR archives.
- The new -ssp switch. If the switch -ssp is specified, 7-Zip doesn’t allow the system to modify “Last Access Time” property of source files for archiving and hashing operations.
- Some bugs were fixed.
- New localization: Swahili.