ALZip vs Zstandard

ALZip is a file compression and extraction program published by ESTsoft. It handles about 40 formats, including ALZ, EGG, ZIP, LZH, TAR, and JAR, and can extract split ALZ, EGG, ZIP, RAR, and ACE archives. Listed features include encryption, split archives, command-line tools, multithreaded ZIP compression, solid and split EGG archives, and Unicode compression. In icon view, users can preview image thumbnails without extracting an archive; linked image viewing requires installing ALSee. ALZip can warn when an archive contains a suspected malicious file and extract it to a safe folder. The PC version can use ALYac to scan compressed files for risks. The product page recommends Windows 11 and 10 for PC and describes a Linux version with similar functions; an Android app is also linked. ESTsoft claims extraction speed can increase by up to 700%, with results depending on format, PC, and environment. The Personal plan costs nothing for qualifying domestic individual users using it noncommercially. Business, education, and public-sector licenses are sold separately, with prices available through the business shopping mall.

Zstandard is a lossless compression algorithm for real-time workloads, with controls that let users shift compression speed and ratio in small increments. Its reference implementation includes a C library and a command-line utility that creates and decodes .zst, .gz, .xz, and .lz4 files. The format is stable and documented in RFC 8878; the implementation is available under BSD or GPLv2. For small, related samples, training can produce a data-specific dictionary to improve compression. The same dictionary must be present for both compression and decompression, and the samples need to be correlated; there is no universal dictionary. The project documents builds with Make, CMake, Meson, Visual Studio, Buck, and Bazel, plus installation using vcpkg and Conan. Community bindings and ports are listed for languages including Python, Rust, Java, C#, JavaScript, Go, PHP, and Swift. Zstandard is free, with a free plan, and supports Linux, Windows, and macOS.