Zstandard Compress
Compress text or encoded binary data to Zstandard online and output the result as Hex or Base64. Read more
What is Zstandard compress?
Zstandard, or zstd, is the lossless compressed-data format described in RFC 8878. It is designed for fast decompression and a wide range of compression-speed tradeoffs. This tool creates a standard Zstandard frame from text or encoded bytes without using an external dictionary.
How to use this tool
Enter text or encoded bytes, choose how the input is decoded, select level 1–22, and output the frame as Hex or Base64. Level 3 is the normal default and is a good starting point. Use Zstandard Decompress to restore the bytes.
Choosing the right format
Base64 is shorter for transporting binary data in text; Hex is easier to inspect. Higher levels can improve compression but require more CPU and memory and may offer little benefit on small or already-compressed input. The same source can have multiple valid Zstandard representations.
Important limitations
Zstandard is not encryption or authentication. This tool does not negotiate or embed a custom dictionary, so dictionary-dependent frames from other systems are a separate interoperability case. Browser and WebAssembly memory limits make native streaming tools preferable for large input and high levels.
Frequently asked questions
Why can another program not open the result?
Decode Hex or Base64 into bytes and confirm the receiver expects a standard Zstandard frame, not .tar.zst, a dictionary-dependent frame, or another format with a .zst suffix.
Are my files uploaded?
No. Compression runs locally. For files or folders, use Zstandard Create.