screenshot of FreeDOS 1.3

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 develop embedded systems. 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.

Create new programs

FreeDOS includes lots of compilers, assemblers, and other 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

Save the date: FreeDOS virtual get-together

Every month, we like to get together for an online meet-up, so we can get to know each other as more than just an email address. We're planning the next virtual get-together on Sunday, December 17 at 11am US/Central. (Use your favorite timezone converter to find your local time.) This month, we are switching to Google Meet for the meeting. As always, we'll share the meeting URL when the meeting starts. We like to alternate topics every month; this month's focus is "technical" - it's a great opportunity to do online debugging, ask for programming help, and otherwise talk about tech issues so we can bring them back to the email list.

A72 assembler version 1.05

A72 is a minimal symbolic assembler for DOS compatible systems. A72 version 1.05 was released a few weeks ago, but we missed the announcement. This has several updates, including: + Listings are generated by default along with binary output + Listings have line numbers + Symbol tables, alphabetically sorted, are appended to listings + More modular construction + HIGH, LOW, INCBIN, ECHO, TITLE, PAGE directives + Lines can be 255 characters long (previously 120-something). You can find the new version at A72 on GitHub.

DosView 1.4 (and 1.5)

DosView is an image converter and viewer for DOS. SuperIlu has released another version with support for new screen resolutions, a change in the command line, and (hopefully) fixed bug in image zooming when the image was not 4:3 and a multiple of the resolution. DosView supports BMP, PCX, JPG, PNG, WEBP, TIFF, JPEG2000, PBM PPM, GIF, PSD, and other image formats. Thanks to SuperIlu for this great image viewer for DOS! Open source, uses several licenses because of libraries. You can find the latest version at DosView on GitHub. We've also mirrored DosView on the FreeDOS Files Archive at Ibiblio, under /util/user/dosview

Updated: SuperIlu has released version 1.5, which includes a fix to the Allegro VESA driver and added screen mode autodetection. Download the latest version from DosView on GitHub. We've also mirrored this on the FreeDOS Files Archive at /util/user/dosview

FreeDOS Edlin 2.23

The FreeDOS Edlin project is the standard line editor in FreeDOS, replacing the classic edlin program from original DOS. Gregory Pietsch has released Edlin 2.23, which fixes a compile time warning when compiling with OpenWatcom C. You can download the source from Edlin on SourceForge. We've also mirrored this version (plus a compiled 16-bit DOS executable, as EDLIN16.EXE) on the FreeDOS Files Archive at Ibiblio under /files/dos/edlin

New libm-0.6 and libmpi-0.2

Gregory Pietsch has released libm-0.6 and libmpi-0.2. libmpi is a Multiple Precision Integer library, and libm is a C math library. Both are public domain. You can find both on the FreeDOS Files Archive at Ibiblio, under /files/devel/libs/libm and /files/devel/libs/libmpi.

Micro-C and other programs, now with source code

Very exciting news! Dave Dunfield has decided to release the source code of over 40 years' work "in the hopes that others may find it useful or maybe learn a few things." This includes the Micro-C compiler, a very nice C compiler for DOS. You can find everything at Source Code Downloads on Dave's website. The source code license isn't an "OSI open source" license, but aims to release the source code for others to use. Thanks Dave!