Zstandard (.zst)
Also known as: zstd, zst file, zstandard compression
Zstandard (zstd) is a modern, lossless compression method designed for fast speed at strong compression ratios. Files compressed with it use the `.zst` extension, and it is widely used in software packaging, file systems, and backups.
- Modern lossless compression, `.zst` extension
- Tuned for fast decompression at strong ratios
- Common in Linux packages, file systems, and backups
What Zstandard does
Zstandard is a lossless compressor: it shrinks data so it takes less space, then restores it exactly when decompressed. A standalone compressed file carries the `.zst` extension, and the same method is built into archive and packaging tools rather than always producing a loose file.
Its design goal is balance — high compression and very fast decompression — with an adjustable level so you can trade a little speed for a smaller result, or the reverse.
Where you encounter it
Zstandard turns up in Linux package managers, file systems, container images, and backup tools, where fast decompression keeps everyday operations snappy. It is a more modern alternative to older methods like gzip.
As with any compression, the space you save depends on the data: already-compressed media like photos and video shrink very little, while text, logs, and code compress well.