Formato de arquivo

Sobre os arquivos GZ

Arquivo Gzip

Lançado em 1992 Por Jean-loup Gailly & Mark Adler

GZ (gzip) é o formato de compressão padrão do mundo Unix/Linux, criado em 1992 como substituto livre do compress original. Comprime um único arquivo (não múltiplos — para isso usa-se .tar.gz). É o algoritmo de compressão usado pela web HTTP (Content-Encoding: gzip), pelo formato PNG internamente e por muitos protocolos de rede.

Família

Archives & Compressed

Extensão

.gz

Tipo MIME

application/gzip

Pode ser usado como

Entrada Saída

A história

COMO NASCEU O
FORMATO GZ.

1951

1992

gzip was born in 1992 when Jean-loup Gailly and Mark Adler needed a free, unpatented alternative to Unix compress (whose LZW algorithm was covered by the same Unisys patent that haunted GIF). They published gzip 1.0 under GPL in October 1992 using a DEFLATE algorithm — a combination of LZ77 and Huffman coding — that became RFC 1951.

gzip quickly became the default compressor on every Unix-like system. The .gz file extension wraps any single file in DEFLATE compression. Pair it with tar and you get .tar.gz (or .tgz), the most common Unix release format. Mark Adler went on to write the zlib library that every modern platform uses; Jean-loup Gailly maintained gzip for decades. Today DEFLATE underpins ZIP, PNG, HTTP Content-Encoding, and dozens of other formats — a humble 1992 algorithm quietly doing the compression for most of the internet.

CURIOSIDADES E
FATOS INTERESSANTES.

gzip's DEFLATE algorithm is the same compression used inside ZIP, PNG, and HTTP Content-Encoding — it powers most of the web.

Mark Adler also wrote zlib, the library every modern platform uses to implement gzip — his name is baked into iOS, Android, Windows, macOS, and Linux.

Every Linux man page (/usr/share/man/) is shipped as a .gz file and decompressed on demand.

HTTP servers send gzipped responses billions of times per second — the "Accept-Encoding: gzip" header is in every request you make.

gzip refuses to compress a file if the result would be larger than the input — it silently stores uncompressed.

VANTAGENS E
LIMITAÇÕES.

Vantagens

Patent-free, royalty-free — that was the whole point in 1992.
Universally supported on every OS.
Fast compression and extremely fast decompression.
Preserves original timestamps and filenames in the header.
Streamable — can compress/decompress over pipes.

Limitações

Compresses one file at a time — needs tar for multi-file archives.
Older algorithm — Zstandard, xz, and brotli all beat it on ratio.
Single-threaded in the reference implementation (pigz fixes this).
Not as aggressive as modern codecs on highly redundant data.

Tamanhos típicos de arquivo

Plain text file

25-40% of original

HTML page

20-30% of original

Source code archive

15-30% of original

Already-compressed file (JPEG, MP4)

99-100% (no gain)

Especificações técnicas

MIME type: application/gzip
Extensions: .gz, .tgz (with tar)
Algorithm: DEFLATE (LZ77 + Huffman coding)
Standard: RFC 1952 (gzip), RFC 1951 (DEFLATE)
Header: 10 bytes: magic, method, flags, mtime, extra, filename, comment, crc, isize

CONVERTER A PARTIR DE
GZ

gz zip gz 7z gz tar gz bz2 gz xz gz lzma gz zst gz lz4

CONVERTER PARA
GZ

tar gz zip gz 7z gz bz2 gz rar gz xz gz cab gz tgz gz jar gz war gz lzma gz zst gz lz4 gz cpio gz ar gz apk gz deb gz rpm gz lz gz iso gz dmg gz snap gz

Casos de uso comuns

Web content compression, tar.gz archives, log file compression.