How to open a .ZST file online
No extra software to download or install.
Pick your .ZST file
Drag it in or click to choose it. We read its contents list first, so it opens right away without unpacking everything.
Browse what's inside
See every file with its size, how much it's compressed and its date, and search by name across all the folders.
Preview or download
Click a file to preview text or images, or save just that one. Need everything? Download it all as a single ZIP.
About .ZST files
What a .ZST file is, and what's inside it.
A ZST file is data compressed with Zstandard (zstd), a fast lossless algorithm made by Facebook/Meta. To open one on Windows use 7-Zip 22.01+ or PeaZip; on Linux or macOS run "zstd -d file.zst". If the file is a .tar.zst archive, use "tar --zstd -xf file.tar.zst" to unpack it.
Programs that open .ZST files
| Full name | Zstandard Compressed File |
|---|---|
| Developer | Meta (Facebook) — Yann Collet |
| First released | 2015 (zstd released by Facebook); format standardized as RFC 8478 (2018) |
| Category | Archives |
| MIME type | application/zstd |
| Signature | 28 B5 2F FD Zstandard frame magic (little-endian 0xFD2FB528) |
Related viewers
Found something inside the archive? Open it here.
Do I have to unpack the whole .ZST file?
No. The viewer reads its table of contents first and only unpacks a file when you click it. That works even with multi-gigabyte archives, because we read just the bytes we need.
Can I open password-protected archives?
Yes, for ZIP (ZipCrypto and AES) and 7Z. You'll be asked for the password,. We can't recover forgotten passwords.
Is my .ZST file uploaded anywhere?
No. The code that unpacks the file is downloaded once and then reused.
Why does a .docx or .apk open as an archive?
Because they are ZIP archives under the hood. Office documents, Android apps, Java programs and EPUB books all use ZIP as their container.
What about split archives (.001, .z01, .part1.rar)?
Multi-part archives need all their parts. Today you can open the first part to see the file list; joining parts is on our roadmap.
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