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. Check license information here: 7-Zip license.
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.
The main features of 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
- Unpacking only: 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.
- 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 79 languages
7-Zip works in Windows 7 / Vista / XP / 2008 / 2003 / 2000 / NT / ME / 98. There is a port of the command line version to Linux/Unix.
On 7-Zip’s Source Forge Page you can find a forum, bug reports, and feature request systems.
We compared 7-Zip with some of the leading archivers.
|Archiver||Mozilla Firefox||Google Earth|
|Compressed size||Ratio||Compressed size||Ratio|
|7-Zip 4.23 (7z format)||4621135||100%||6109183||100%|
|WinZip 10.0 beta (maximum-PPMd)||5277118||114%||8200708||134%|
|7-Zip 4.23 (zip format)||6222627||135%||8909446||146%|
|WinZip 10.0 beta (maximum-portable)||6448666||140%||9153898||150%|
Compression ratio results are very dependent upon the data used for the tests. Usually, 7-Zipcompresses to 7z format 30-70% better than to zip format. And 7-Zip compresses to zip format 2-10% better than most of other zip compatible programs.