7-Zip Portable is an open-source file archiver, an application used primarily to compress files. 7-Zip uses its own 7z archive format, but can read and write several other archive formats. The program can be used from a command-line interface as the command p7zip, as a graphical user interface, or with a window-based shell integration. 7-Zip began in 1999 and is developed by Igor Pavlov. 7-Zip is open-source software. Most of the source code is under the GNU LGPL license. The unRAR code is under the GNU LGPL with an “unRAR restriction”, which states that developers are not permitted to use the code to reverse-engineer the RAR compression algorithm.
- The 256-bit AES cipher. Encryption can be enabled for both files and the 7z directory structure. When the directory structure is encrypted, users are required to supply a password to see the filenames contained within the archive. WinZip-developed zip file AES encryption standard is also available in 7-Zip to encrypt ZIP archives with AES 256-bit, but it does not offer filename encryption as in 7z archives.
- Volumes of dynamically variable sizes, allowing use for backups on removable media such as writable CDs and DVDs.
- Usability as a basic orthodox file manager when used in 2-panel mode.
- Multiple-core CPU threading settings can be configured.
- The ability to attempt to open EXE files as archives, allowing the decompression of data from inside many “Setup” or “Installer” or “Extract” type programs without having to launch them.
- The ability to unpack archives with corrupted filenames, renaming the files as required.
- The ability to create self-extracting single- (but not multi-) volume archives.
- Command-line interface.
- Graphical user interface. The Windows version comes with its own GUI, however p7zip uses the GUI of the Unix/Linux Archive Manager.