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Extract/Unzip/Uncompress/Open gz/gzip Files with Freeware

GZIP/GZ standing for GNU zip. It is based on the DEFLATE algorithm, which is a combination of Lempel-Ziv (LZ77) and Huffman coding. The program was created by Jean-Loup Gailly and Mark Adler as a free software replacement for the compress program used in early Unix systems, and intended for use by the Project. Its main advantages over compress are much better compression and freedom from patented algorithms. It has been adopted by the GNU project and is now relatively popular on the Internet. Version 0.1 was first publicly released on October 30, 1992, and version 1.0 followed in February 1993.

The format was designed to allow single pass compression without any backwards seek, and without a priori knowledge of the uncompressed input size or the available size on the output media. If input does not come from a regular disk file, the file modification time is set to the time at which compression started.

The gzip format allows multiple compression methods (although gzip currently supports only the 'deflate' method). It must be possible to detect the end of the compressed data with any compression method, regardless of the actual size of the compressed data. In particular, the decompressor must be able to detect and skip extra data appended to a valid compressed file on a record-oriented file system, or when the compressed data can only be read from a device in multiples of a certain block size. (This condition is not fulfilled by the 'compress' program, which has no way of determining the end of compressed data from the data itself.)

Gzip is based on the DEFLATE algorithm, which is a combination of LZ77 and Huffman coding. DEFLATE was intended as a replacement for LZW and other patent-encumbered data compression algorithms, which, at the time, limited the usability of compress and other popular archivers.

"Gzip" is often also used to refer to the gzip file format, which is:

  • a 10-byte header, containing a magic number, a version number and a time stamp
  • optional extra headers, such as the original file name
  • a body, containing a DEFLATE-compressed payload
  • an 8-byte footer, containing a CRC-32 checksum and the length of the original uncompressed data

In general, gzip file ends with a .gz extension.

To extract/unzip.uncompress/open gzip/gz files, we recommend you a popular and 100% free software - 7-Zip. 7-Zip is an open source freeware. You can use 7-Zip on any computer, including a computer in a commercial organization. You don't need to register or pay for 7-Zip.


To associate gz/gzip file to 7-Zip in Windows, please click menu "Tools" -> "Options" -> "System", and then check "gz" and "gzip", and then click OK.

Associate gz/gzip to 7-Zip

If you're using Windows 7 or Vista, you must run 7-Zip in administrator mode. Please right-click the icon of 7-Zip File Manager, and then click Run as administrator.

In File Explorer, you could right-click on gz/gzip file and choose "7-Zip" -> "Open archive" or "Extract files" to open/extract gz/gzip file.

7-Zip freeware works in Windows 10 / 8 / 7 / Vista / XP / 2008 / 2003 / 2000 / NT / ME / 98.

The 7-Zip is absolutely virus, spyware, marlware, and adware free. It's safe to install.




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