ZIP vs TAR vs GZ vs 7z: What’s the Difference?

The key difference is that these formats split the job of “archiving” (bundling many files into one) and “compression” (making it smaller) differently: ZIP does both together, TAR only bundles, GZ only compresses a single stream, and 7z bundles and compresses with a stronger algorithm. That’s why you see .tar.gz — TAR to bundle, GZ to compress the bundle. Once you see the archive-vs-compress split, the whole family makes sense. Here’s each one.

This guide compares the four formats and shows where the TAR extractor and ZIP extractor fit.

Two jobs: archiving and compression

“Putting files in an archive” is really two separate tasks:

• Archiving — combining many files and folders into one file, preserving names and structure.
• Compression — encoding data so it takes less space.

Different formats handle these differently, and that single fact explains all the differences below.

ZIP — archive + compress, together

ZIP does both jobs in one format, compressing each file individually and storing them with a directory at the end. Because each file is compressed separately, you can pull out one file without unpacking the whole archive (random access). It’s the universal default — every operating system opens ZIP natively — at the cost of slightly weaker compression than newer formats.

TAR — archive only, no compression

TAR (“tape archive”) only bundles. A .tar concatenates files into one, preserving Unix permissions, ownership and structure faithfully — but it doesn’t make anything smaller. On its own a TAR is the same size as its contents combined. It’s the standard bundling step in the Unix/Linux world, which is why it’s usually paired with a compressor.

GZ (gzip) — compress one stream

GZ only compresses, and only a single stream of data — it has no concept of multiple files. That’s why you rarely see a bare .gz of many files. Instead, TAR bundles everything into one stream and GZ compresses that stream, giving .tar.gz (or .tgz): TAR’s faithful bundling plus gzip’s compression. It’s the standard way software is distributed on Linux.

7z — bundle + compress, hardest

7z does both jobs like ZIP but with the stronger LZMA algorithm and “solid” compression (compressing files together rather than separately), which usually produces the smallest archive of the four. The trade-offs: it’s slower, solid compression means less efficient single-file extraction, and it isn’t built into every OS, so the recipient may need a tool that supports it.

At a glance

Which should you use?

• Sharing with anyone — ZIP, for universal support.
• Linux software or backups — .tar.gz, the ecosystem standard.
• Smallest possible size — 7z, if you know the recipient can open it.
• Compressing one file — gzip is fine; for many files, bundle with TAR first.

To open a TAR, GZ or TAR.GZ archive, use the TAR extractor; for ZIP, the ZIP extractor. Both run in your browser, so archives are never uploaded.

Frequently asked questions

What’s the difference between ZIP and TAR?
ZIP both bundles and compresses files; TAR only bundles them, with no compression. That’s why TAR is usually paired with gzip as .tar.gz.

Why are files called .tar.gz?
Because two steps were applied: TAR bundled the files into one stream, then gzip compressed that stream. TAR handles the many-files part; gzip handles the shrinking.

Is 7z better than ZIP?
7z usually compresses smaller thanks to LZMA and solid compression, but it’s slower and not built into every operating system. ZIP is more universal.

Can gzip compress multiple files?
No. Gzip compresses a single stream, so multiple files are first bundled with TAR, giving .tar.gz.

Which archive format is most compatible?
ZIP — every major operating system opens it without extra software.

Related reading

• Why your ZIP file won’t open
• File extension vs MIME type

Last updated: 16 August 2026.