7-Zip is free software with open source. The most of the code is under the GNU LGPL license. Some parts of the code are under the BSD 3-clause License. Also there is unRAR license restriction for some parts of the code. Read 7-Zip License information.
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.
High compression ratio in 7z format with LZMA and LZMA2 compression
Supported formats:
Packing / unpacking: 7z, XZ, BZIP2, GZIP, TAR, ZIP and WIM
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 87 languages
7-Zip works in Windows 10 / 8 / 7 / Vista / XP / 2016 / 2012 / 2008 / 2003 / 2000 / NT.
Reference: https://www.7-zip.org/
7Zip has been reported to be the most popular file achieving software in the Asia Pacific region.