Zstandard Create (Compress)

Compress a file as Zstandard or create a tar.zst archive from multiple files and folders directly in your browser. Read more

What is Zstandard create?

Zstandard is the fast lossless format specified in RFC 8878. It compresses byte streams rather than maintaining a multi-file directory. This tool creates .zst for one file; for multiple files or folders it creates TAR first and compresses that stream as .tar.zst or .tzst.

How to use this tool

Add files or folders, review their relative paths, select level 1–22, and choose a matching filename. Use .zst for one compressed stream and .tar.zst or .tzst when TAR holds multiple entries. Use Zstandard Extract to restore it.

Output modes

  • Download (default) keeps the generated result in browser memory and provides a reusable Download button. You can rename the download without recompressing while the content is unchanged.
  • Save directly to a file writes the archive incrementally to a local file you choose. It uses less peak memory for large outputs, but there is no repeat Download button without creating again. Availability depends on browser support for the File System Access API in a secure context.

Files are still processed locally and are not uploaded.

Choosing the right format

Zstandard supplies compression; TAR preserves names and folders. Level 3 is the normal default. Higher levels may reduce size but cost more CPU and memory, with diminishing returns for small or pre-compressed files.

Important limitations

Neither Zstandard nor TAR encrypts data or paths. Download mode retains the generated output in memory. Direct Save avoids retaining the complete output, though codec state and bounded chunks still use memory. Use native streaming tools for large collections, specialized dictionaries, or exact Unix metadata and link preservation.

Frequently asked questions

Why can another program not open the result?

Determine whether the result is one .zst stream or Zstandard-compressed TAR. Decompressing .tar.zst produces .tar, which must then be extracted. A custom-dictionary workflow requires compatible dictionary handling on both ends.

Are my files uploaded?

No. Selected files are archived and compressed locally in the browser.

Zstandard Contents

Drag and drop files or folders here, or use the buttons above.

Files are processed locally and are not uploaded.
0 items0 B
Add files or folders to create a Zstandard archive.

Files already exist

Choose how to handle items with the same path in this Zstandard.

    Clear Zstandard contents?

    All files and folders currently added to this Zstandard will be removed.

    Settings
    Create