Open 7ZIP file

The 7zip file extension is used for native file format of 7-ZIP archiver.

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

The main features of 7z file format:
- Open architecture
- High compression ratio
- Strong AES-256 encryption
- Ability of using any compression, conversion or encryption method
- Support for very large files with sizes up to 16000000000 GB
- Unicode file name support
- Solid compression ratio
- Archive headers compression

7z file format has an open architecture, so it can support any new compression methods. LZMA is the default and general compression method of 7z file format.
The main features of LZMA are:

• Variable dictionary size (up to 4 GB)
• Compression speed: about 1 MB/s on 2 GHz CPU
• Decompression speed: about 10-20 MB/s on 2 GHz CPU
• Small memory requirement for decompression (depend from dictionary size)
• Small code size for decompression: about 5 KB
• Supports multi-threading and P4's hyper-threading

The LZMA compression algorithm is very suitable for embedded applications. LZMA is released under the terms of the GNU LGPL.

7-Zip supports encryption with the AES-256 algorithm. This algorithm uses a cipher key with a length of 256 bits. To create that key, 7-Zip runs a derivation function based on a SHA-256 hash algorithm.

A key derivation function produces a derived key from the text password entered by the user. To increase the cost of an exhaustive search to crack a password, 7-Zip uses a large number of iterations when it produces a cipher key from a password.

7z file format was developed as as part of the 7-Zip compression utility distributed under the GNU LGPL.

MIME types:
application/x-lzma