Convert TAR to TAR.GZ — Free Online Converter

TAR is an uncompressed archival format that bundles files and directories into a single stream. TAR.GZ applies gzip (DEFLATE) compression on top of a TAR archive, producing the compressed tarball format that serves as the standard for source distribution, package management, and file bundling across the entire Unix/Linux ecosystem.

Converting TAR to TAR.GZ is simply adding gzip compression to an existing tar archive. This is the most fundamental compression operation in Unix — equivalent to running `gzip archive.tar` — and produces the format expected by GitHub releases, npm, pip, gem, Debian source packages, and virtually every open-source distribution channel.

An uncompressed TAR file is unnecessarily large for storage and transfer. Adding gzip compression typically reduces the archive to 15-40% of its original size, making it practical for web download, email attachment, and version-controlled storage. The .tar.gz format is so universal in Unix that many tools silently expect it — uploading an uncompressed .tar to a package registry may produce errors.

Gzip specifically (as opposed to bzip2 or xz) is preferred for its extraction speed. While not the strongest compressor, gzip decompresses faster than any common alternative, making it ideal for CI/CD pipelines, Docker layer extraction, and any workflow where extraction latency matters more than a few extra megabytes of archive size.

The conversion reads the TAR file as a raw byte stream and pipes it through gzip compression using the DEFLATE algorithm (LZ77 sliding window + Huffman coding). No extraction or parsing of the TAR's internal structure is performed — the entire TAR is treated as an opaque data stream for compression purposes. The output wraps the compressed data in a gzip container with a 10-byte header (magic number, method, flags, timestamp), the DEFLATE stream, and an 8-byte trailer (CRC32 + original size). Compression level defaults to 6.