Convert TAR to GZ — Free Online Converter

TAR bundles files and directories into a single uncompressed stream, preserving Unix metadata including permissions, ownership, and symlinks. GZ (Gzip) applies DEFLATE compression to a single data stream. The combination of TAR + GZ produces the ubiquitous .tar.gz format — the standard for source distribution on Unix/Linux systems.

Converting TAR to GZ compresses your uncompressed tar archive with gzip, producing the .tar.gz (or equivalently .tgz) format that every Unix system can extract natively. This is the most common archive compression operation in the Unix world — it takes a raw file bundle and makes it practical for storage and transfer.

Plain TAR files are impractically large for distribution and storage. A source code directory that unpacks to 100 MB as TAR typically compresses to 15-25 MB as .tar.gz. This 75-85% size reduction makes the archive practical for downloading, email attachment, and storage. Virtually every open-source project, Linux distribution, and Unix package system uses .tar.gz as their primary distribution format.

Gzip compression is the fastest standard compression option for tar archives, offering the best balance of speed and compression ratio for everyday use. While bzip2 and xz compress better, gzip decompression is significantly faster — a critical advantage when extracting on CI servers, embedded systems, or any time-sensitive pipeline.

The TAR file is read as a continuous byte stream and piped through the gzip compressor. Gzip applies the DEFLATE algorithm (LZ77 + Huffman coding) with a 32 KB sliding window, processing the tar data sequentially. The output includes a gzip header (magic bytes 1f8b, compression method, timestamp, OS identifier), the DEFLATE-compressed data, and a trailer (CRC32 checksum of the original data plus original size modulo 2^32). Default compression level is 6 (balanced speed/ratio).