bzip2

Free plan LinuxWindows

What bzip2 is

bzip2 is a freely available data compressor for creating and reading compressed files. It supports BZ2 (.bz2), BZ (.bz), TBZ2 (.tbz2), and TBZ (.tbz) formats and includes command-line tools. The maker says its compression typically comes within 10% to 15% of the best available PPM-family techniques; it also describes compression as about twice as fast and decompression as six times as fast as those techniques. Its limited media-error recovery may allow undamaged portions of a damaged file to be decompressed. The libbzip2 library lets programs read and write .bz2 files or compress data in memory. Command-line flags are similar to GNU Gzip's, and the distribution should compile unmodified on Unix and Win32 systems. The project dates to 1996 and is open source under a BSD-style license. The official site lists version 1.0.8 as the current stable version and offers source code, not executables. Its source tarball includes documentation in HTML, PDF, PostScript, and Unix man-page formats.

Who it suits

bzip2 suits users who need a free command-line compressor or developers who want a library for .bz2 files or in-memory compression. It is listed for Unix/Linux and Win32 systems.

What it does well

Free and open source under a BSD-style license
Includes command-line tools and libbzip2
Limited recovery may decompress undamaged file portions
Source tarball includes documentation in four formats

What to know first

Downloads provide source code, not executables
Archive encryption is not supported
Split archives are not supported
Author offers no guarantee about patent status

Plans

Plan	Billed and limits	Price
bzip2	Freely available; source code distribution	Free

As sourceware.org lists them, read 7 Oct 2026. The maker's own page has the final word.

Getting started

Open the official bzip2 website.
Get the source code from the downloads page; no executables are provided there.
Build it with an ANSI C compiler and at least 8 megabytes of spare memory.
Use the command-line tools, or use libbzip2 from a program to read or write .bz2 files or compress data in memory.

Verdict

bzip2 offers compression tools and a library, with limited recovery support and broad source portability noted by its maker. Users seeking ready-made executables should note that the downloads page provides source code only.

Questions

Is bzip2 free?

Yes. Its listed plan is free, and the maker describes it as freely available.

Which platforms does bzip2 support?

The listed platforms are Linux and Windows; supported platforms are also described as Unix/Linux and Win32.

Is bzip2 open source?

Yes. The maker describes it as open source under a BSD-style license.

Which archive formats does it support?

BZ2 (.bz2), BZ (.bz), TBZ2 (.tbz2), and TBZ (.tbz).

Does bzip2 provide executables for download?

The downloads page provides source code and says executables are not available there.

Does bzip2 support archive encryption?

No. Archive encryption and split archives are both listed as unsupported.

Facts from bzip2's own pages

Compatibility: Its command-line flags are similar to GNU Gzip's, and the distribution should compile unmodified on Unix and Win32 systems. · sourceware.org, 7 Oct 2026
Compression: The maker says bzip2 typically compresses files to within 10% to 15% of the best available PPM-family techniques. · sourceware.org, 7 Oct 2026
Current stable version: The official site lists bzip2 1.0.8 as the current stable version. · sourceware.org, 7 Oct 2026
Documentation: The source tarball includes pre-built documentation in HTML, PDF, PostScript, and Unix man-page formats. · sourceware.org, 7 Oct 2026
Downloads: The downloads page provides source code and says no executables are available there. · sourceware.org, 7 Oct 2026
Error recovery: bzip2 supports limited recovery from media errors and may decompress undamaged parts of a damaged file. · sourceware.org, 7 Oct 2026
Founded: 1996 · sourceware.org, 28 Sept 2026
Library: libbzip2 provides an interface for programs to read and write .bz2 files or compress data in memory. · sourceware.org, 7 Oct 2026
License: The maker describes bzip2 as open source under a BSD-style license. · sourceware.org, 7 Oct 2026
Patent statement: The author says he believes bzip2 does not use patented algorithms but cannot guarantee this because he has not carried out a patent search. · sourceware.org, 7 Oct 2026
Purpose: bzip2 is a freely available, high-quality data compressor. · sourceware.org, 7 Oct 2026
Release signing: The official downloads page says releases are PGP signed and provides a signature file and signing key. · sourceware.org, 7 Oct 2026
Resource requirement: The downloads page says building has a good chance of success with an ANSI C compiler and at least 8 megabytes of spare memory. · sourceware.org, 7 Oct 2026
Speed: The maker says bzip2 is around twice as fast at compression and six times faster at decompression than those PPM-family techniques. · sourceware.org, 7 Oct 2026

Where bzip2 stands on Freedom251

File Compression Software#8 of 36