screenshot of FreeDOS 1.4

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

Play DOS games on FreeDOS! We include lots of fun games in the distribution. Or play your favorite classic games, like Wolfenstein 3D, Doom, Commander Keen, Jill of the Jungle, Duke Nukem, and many others!

Run applications

Run your favorite DOS programs with FreeDOS. Just install your DOS application under FreeDOS like you would any other DOS application and you'll be good to go.

For developers

We include lots of open source compilers, assemblers, debuggers, and editors so you can create your own DOS programs. We also share our source code under an open source license, so you can modify FreeDOS itself.

What’s New

FreeDOS kernel 2044

Jeremy Davis has been collecting changes to the FreeDOS kernel, and recently announced a new version. Jeremy writes: "I haven't had the time to have this where I'd like it to be, but there are so many improvements from others since the last release .. I recommend using the latest release (or even automatic builds from GitHub for testing" The FreeDOS Kernel (kernel.sys) is the core part of FreeDOS. Kernel 2044 is an incremental maintenance release with a mix of build fixes, boot/runtime edge‑case fixes, and compatibility updates. Thanks to everyone who contributed to this version, including Andrew Bird, Bernd Böckmann (boeckmann), Jeremy Davis, C. Masloch (ecm), Tee-Kiah Chia (tkchia), Sava (lpproj), Stas Sergeev (stsp), Jiri Malak (jmalak), Tom Ehlert, and others!

Jeremy has a long list of changes on his Kernel 2044 release page on GitHub. A few highlights include: * Build and project maintenance * Boot / initialization * Environment and CONFIG.SYS handling * File system, disk I/O, and large‑file edge cases * FCB compatibility (older DOS APIs) * Redirector / networking interactions * Path handling / TRUENAME * Utilities / tooling. Most importantly, this version supports Windows 3.x Enhanced Mode with updates aimed at improving Windows 3.x Enhanced Mode compatibility, and critical patch table handling and minor IOCTL behavior adjustments. We've also mirrored the new version at the FreeDOS Files Archive at Ibiblio, under /files/dos/kernel

FDNPKG16 version 0.99.8253a

Victoria Crenshaw has been working on updates to FDNPKG16, a network-aware package manager for FreeDOS. Victoria shared version 0.99.8253a with these updates: * fixed a bug in dumpcfg with install sources flag being inverted * httpget.exe unlinks files that fail to download * fixed a lot of copyrights headers and variable names * fdinst16.exe has multi-package install and remove features. You can download the latest version that is stable at fdnpkg16.zip {zip file} or you can try a development version {zip file}. Victoria is looking for people to test the latest version, and to suggest changes or improvements.

Calvin 2.5

Ben Collver recently announced an update to the Calvin vi editor. If you like Unix vi editor, you might like Calvin. The changes in this version are key mapping: * End -- Map to $ instead of L * Home -- Map to 0 instead of H * R -- Replace mode * :previous -- edit the previous file from the argument list * { or }-- move backward or forward by paragraph. This editor requires 128K of memory, and also supports EGA 43-line and VGA 50-line modes. Get the new version from Archive.org and the source code from the Ben's Calvin repo.

Fontana version 1.2

Thanks to Laaca for sharing a new version of the Fontana font editor. Laaca writes: "Fontana is tool for developers. It is a bitmap font editor (with ability to import from some vector formats) which allows you to create, convert and edit fonts stored in many file formats. It shares some portions of code with my older project Kasmar which also was a font editor much simpler and with many limitations." Changes in 1.2 include: + support for unproportional (monospaced) mode + CPI archives can be saved also in WinNT subformat + default font for cp852 now contains euro symbol + overview of undefined characters in given range. You can download the new version from Laaca's website

lDebug release 10

After more than a year since the last release, there now is release 10 of lDebug (that's a small L). This is an advanced line-oriented debugger based on FreeDOS Debug/X. The new release contains some bugfixes and a few added features. It newly uses an LZEXE-based compression format for its online help pages and the packed Extension for lDebug (ELD) library. The freedos-user list has a longer announcement. Get it from the project's web page or from the FreeDOS Files Archive at ibiblio, under /dos/debug/ldebug

Calvin 2.4

Calvin is a very small and fast version of the vi editor for 16-bit DOS. Ben Collver has compiled Calvin 2.4 and made it available. From Ben's note: "There is really only one change in this release: the status message from ^G now prints the current column as well as the line. The only real reason for this release is to port the source code from Borland Turbo-C and A86 to the free Watcom compiler toolchain, which is shipped with FreeDOS." Get the new version from Archive.org