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.
Features
- 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: APFS, AR, ARJ, CAB, CHM, CPIO, CramFS, DMG, EXT, FAT, GPT, HFS, IHEX, ISO, LZH, LZMA, MBR, MSI, NSIS, NTFS, QCOW2, RAR, RPM, SquashFS, UDF, UEFI, VDI, VHD, VHDX, VMDK, 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 87 languages
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 2-8 MB/s on 4 GHz CPU (2 cpu threads version).
- Decompressing speed: about 30-100 MB/s on 4 GHz CPU (1 cpu thread).
- Small memory requirements for decompressing (depend from dictionary size)
- Small code size for decompressing: about 5 KB