Welcome to FreeDOS
FreeDOS is an open source DOS-compatible operating system that you can use to play classic DOS games, run legacy business software, or write new DOS programs. Any program that works on MS-DOS should also run on FreeDOS.
** Play classic games
You can play your favorite DOS games on FreeDOS. And there are a lot of great classic games to play: Wolfenstein 3D, Doom, Commander Keen, Rise of the Triad, Jill of the Jungle, Duke Nukem, and many others!
** Run applications
You can run your favorite DOS programs with FreeDOS. Or use FreeDOS to run a lega…
Welcome to FreeDOS
FreeDOS is an open source DOS-compatible operating system that you can use to play classic DOS games, run legacy business software, or write new DOS programs. Any program that works on MS-DOS should also run on FreeDOS.
** Play classic games
You can play your favorite DOS games on FreeDOS. And there are a lot of great classic games to play: Wolfenstein 3D, Doom, Commander Keen, Rise of the Triad, Jill of the Jungle, Duke Nukem, and many others!
** Run applications
You can run your favorite DOS programs with FreeDOS. Or use FreeDOS to run a legacy DOS application. Just install your DOS program under FreeDOS like you would any DOS application and you’ll be good to go.
** For developers
FreeDOS includes lots of programming tools so you can create your own DOS programs. You can also modify FreeDOS itself, because we include the source code under an open source license.
What’s New
Highlighting DOS in #DOScember
2025-12-29 1:07pm
jSH version 0.99
2025-12-14 2:19pm
SuperIlu just published v0.99 of jSH, a JavaScript scripting environment for DOS. This is the ‘little’ text-mode brother to DOjS, released not long ago. New features in this version include: - fixed Screen object - fixed CGets() - added missing include - updated zip, mbedTLS and curl. You can find the new version at jSH on GitHub.
Zork I, II, and III go open source
2025-12-03 3:36pm
Microsoft’s Open Source Programs Office (OSPO), Team Xbox, and Activision recently announced that the classic games Zork I, Zork II, and Zork III are now released as open source software, under the MIT License. If you don’t know Zork, it was an extremely popular series of text-based adventure games, released by Infocom on a variety of platforms including personal computers. You used your imagination and typed commands to navigate and take actions, with clever puzzles and world-building. Zork’s Z-Machine interpreter was also a platform to create other, similar text adventure games like Hitchhiker’s Guide to the Galaxy. You can find Zork I, Zork II, and Zork III at the Historical Source archive on GitHub.
DOjS v1.14.0
2025-12-03 3:21pm
SuperIlu has released a new version of DOjS, the javascript environment for DOS. Version 1.14.0 has several fixes and additions, but mostly for win32 users, with only a few updates for DOS users: * fixed error message for library loading in win32 * fixed SQLite3 database opening in win32 * return empty object from GetNetworkInterfaces() on win32 * fixed curl on win32 * updated zip to 0.3.5 * improved documentation * updates to libraries. Download the new release at DOjS 1.14.0 at GitHub.
Packet Drivers Collection for FreeDOS
2025-10-28 1:41pm
In 1986 FTP Software Inc. created the PC/TCP Packet Driver specification which defined an API for sending and receiving packets over networking devices. Inside the packet driver is code to talk to a specific piece of hardware. That hardware might be a network adapter, an Ethernet chipset connected through the parallel port, or even just a plain serial port. A packet driver makes the hardware and network accessible in an easy manner. Omar Yabar has collected a ton of DOS-era packet drivers in one place, so you can easily download the one you want. Find them at the Packet Drivers Collection. We can’t include these in the FreeDOS distribution because they are not open source, but we really appreciate the hard work Omar has done to collect these for DOS fans to use!
NASM 3.01
2025-10-28 1:37pm
NASM is the Netwide Assembler, an open source assembler for the x86 CPU architecture, including DOS. There’s a new update available now: version 3.01 mostly contains fixes such as: * The condition after %if or %elif would be evaluated while output is suppressed after %exitrep or %exitmacro * Fix encoding of TCVTROWPS2PHL * The unofficial but obvious alternate form TEST reg,mem was not accepted by NASM 3.00 * A new %selbits() preprocessor function and command line option * Define additional permissive patterns and fix several opcode bugs * Fix parsing of two-operand forms of x87 instructions * And other fixes. See the NASM documentation for more. Download the new version from the official releasebuilds 3.01