What is a .zst file?
Zstandard Compressed File · Archive · Meta (Facebook) · 2016
Zstandard (.zst) is a modern compression format that is very fast while still compressing well. It has spread quickly through Linux packaging, filesystems and databases, often seen as .tar.zst.
What is a .zst file used for?
A .zst file begins with the little-endian magic 28 B5 2F FD. Zstd's headline feature is speed: it decompresses far faster than xz at similar ratios, which is why package managers and filesystems adopted it.
As a single-stream compressor it pairs with tar for bundles, giving .tar.zst. Modern archive tools and the zstd command handle it.
How to open a .zst file
The .zst format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .zst file.
Windows
- 7-Zip (recent)
- PeaZip
- zstd
macOS
- Keka
- zstd (Homebrew)
Linux
- zstd
- tar
- Ark
How to convert a .zst file
You can convert a .zst file to xz, gz, zip using a conversion tool or the export menu of an app that opens it.
.zst file signature (magic bytes)
Programs recognise a .zst file by the bytes at the start of the file, not by its name. These are the signatures for Zstandard. For a full breakdown, see the Zstandard file signature page.
| Hex signature | Offset | Note |
|---|---|---|
| 28 B5 2F FD | 0 | Zstandard frame magic |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .zst file?
Zstandard (.zst) is a modern compression format that is very fast while still compressing well. It has spread quickly through Linux packaging, filesystems and databases, often seen as .tar.zst.
How do I open a .zst file?
Use the zstd command (zstd -d file.zst), a recent 7-Zip or PeaZip on Windows, or Keka on Mac. A .tar.zst unpacks with tar --zstd -xf.
Is Zstandard better than gzip or xz?
It decompresses much faster than xz at similar sizes, and beats gzip on both. That speed is why Linux packaging and filesystems switched to it.
What makes .zst files popular?
A rare mix of high compression and very fast decompression, plus tunable levels, which suits package managers, backups and real-time systems.
Related formats
Sources
Details on this page were checked against authoritative references: