7-Zip is a free but powerful file archiver with a high compression ratio. You can use it on any computer (including commercial organizations).

Platform: Windows, Linux

7-Zip has a high compression ratio and also supports over 50 different languages. You can use 7-zip for free on any computer (including commercial organizations).

Main features of 7-Zip

• High compression ratio in new 7z format with LZMA compression
• Supported formats:
  • Packing / unpacking: 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.
• 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 74 languages

Archive Formats

7-Zip supports (both compressing and decompressing) a number of archive formats. It can compress files and folders to 5 archive formats (see Compressing column) and decompress all archive formats in table below.

The decompressing for a large number of formats is a very useful feature. Normally files downloaded from the web can be in various compressed formats, but most common formats I come across include zip, rar, tar, gz, and iso. With 7-Zip, I can decompress them without having to install additional software.

Format	Compressing	Decompressing	Filename Extensions
7z	Yes	Yes	7z
ZIP	Yes	Yes	zip
GZIP	Yes	Yes	gz gzip tgz
BZIP2	Yes	Yes	bz2 bzip2 tbz2 tbz
TAR	Yes	Yes	tar
RAR	?	Yes	rar
CAB	?	Yes	cab
ARJ	?	Yes	arj
Z	?	Yes	z taz
CPIO	?	Yes	cpio
RPM	?	Yes	rpm
DEB	?	Yes	deb
LZH	?	Yes	lzh lha
SPLIT	?	Yes	001 002 ...
CHM	?	Yes	chm chw hxs
ISO	?	Yes	iso
COMPOUND	?	Yes	msi doc xls ppt
WIM	?	Yes	wim swm
NSIS	?	Yes	exe

Use 7-Zip

Most of the operations in 7-Zip can be executed by using keyboard shortcuts or by right-clicking on a file or folder and selecting the appropriate command from the context menu. You can always open all archives with 7-Zip via your right-click context menu. Below is a screenshot of the right-clicking popup menu items.

7-Zip also provides a command line version as well as 7z.dll that can be used in a third party application to add file archive function.

Test archive

7-Zip can be used to test the integrity of archived files. It's always a good idea to test the archive before you actually trust it but later find it can't be used. To test an archive, right click on the archive filename in Windows Explorer. Inside the 7-Zip pop-up context menu, select "Test archive".

7-Zip supports over 50 different languages. You can change 7-Zip to use your preferred language by going to Tools -> Options, and then select Language tab.

Go to 7-Zip website to download or see more detailed information.