File Extension Library


.7-Z File Extension

  • Developer by: Igor Pavlov
  • Category: Archive and compressed Files

What are .7-Z files and how to open them?

Can't open .7-Z file? Are you wondering what it contains? On our site we will explain to you what this file is, what it is used for and what software opens the .7-Z file.

What is a .7-Z file extension?

.7-Z file extension is created by Igor Pavlov. .7-Z has been classified as Archive and compressed Files.

.7-Z is 7z compressed archive

Default file extension for 7z compressed archive file is 7z.

7z is the new backup, archive - compressed file 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
- Support for very large files with sizes up to 16000000000 GB
- Unicode file name support
- Solid compression ratio
- Archive headers compression

7z has an open architecture, so it can support any new compression method, too. The following methods currently are integrated into 7z:

LZMA Improved and optimized version of LZ77 algorithm PPMD Dmitry Shkarin's PPMdH with small changes BCJ Converter for 32-bit x86 executables BCJ2 Converter for 32-bit x86 executables BZip2 Standard BWT algorithm Deflate Standard LZ77-based algorithm

LZMA is the default and general compression method of 7z format. The main features of LZMA are:

  • High compression ratio
  • 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 is part of the 7-Zip program distributed under the GNU LGPL.


How to open:

Use some of the suggested applications below 7z file extension description.

How to convert:

Use 7-zip to convert 7z archive to another archive format.

How to fix problems with .7-Z files

  1. You need to update the application that you normally use to open .7-Z files. Only the latest version of the software supports the current .7-Z file format
  2. You need to check the .7-Z file for viruses. To do this, you need to scan it with a popular antivirus (Norton, Nod32, Kaspersky, Dr.Web, etc.)