A TZST file contains multiple files in a Unix .TAR archive that is compressed with the Zstandard (zstd) compression algorithm to reduce the file size. It is the shorthand version of the compound extension tar.zst similar to the .TGZ, .TBZ2, and .TXZ files. TZST files are commonly used on Unix and Linux systems. The best software I found to extract .tzst compressed files is PeaZip. PeaZip is a free file archiver utility, based on Open Source technologies of 7-Zip / p7zip archiver, Facebook Zstandard fast compressor, FreeArc, Google Brotli fast compressor, PAQ family of compressors, secure file archiving and encryption PEA project, and other Free Software file compression tools. Click Here to download and see more features of PeaZip. With this you can decompress an archive file having .zst or tar.zst.