The main features of 7-Zip
* High compression ratio in new 7z format with LZMA compression
* Supported formats:
o Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
o 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

7-Zip works in Windows 98/ME/NT/2000/XP/Vista. 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.

7z is the new archive format, providing high compression ratio.

The main features of 7z format:
* Open architecture
* High compression ratio
* Strong AES-256 encryption
* Ability of using any compression, conversion or encryption method
* Supporting files with sizes up to 16000000000 GB
* Unicode file names
* Solid compressing
* Archive headers compressing

LZMA is default and general compression method of 7z format. The main features of LZMA method:
* High compression ratio
* Variable dictionary size (up to 4 GB)
* Compressing speed: about 1 MB/s on 2 GHz CPU
* Decompressing speed: about 10-20 MB/s on 2 GHz CPU
* Small memory requirements for decompressing (depend from dictionary size)
* Small code size for decompressing: about 5 KB
* Supporting multi-threading and P4's hyper-threading

LZMA compression algorithm is very suitable for embedded applications. LZMA is released under the terms of the GNU LGPL. LZMA is also available under a proprietary license for those who can not use the GNU LGPL in their code. If you want to use LZMA code, you can ask consultations, custom code programming and required developer licenses from page for support: Send message to LZMA developer. Check also information about LZMA SDK.

7-Zip also supports encryption with AES-256 algorithm. This algorithm uses cipher key with length of 256 bits. To create that key 7-Zip uses derivation function based on SHA-256 hash algorithm. A key derivation function produces a derived key from text password defined by user. For increasing the cost of exhaustive search for passwords 7-Zip uses big number of iterations to produce cipher key from text password.

Release date v4.65 - 2009-02-03
- 7-Zip File Manager now can calculate SHA-256 checksum.
- Some bugs were fixed.


Download Link