The original Doom game engine source code was released into the public domain back in 1997, since then there have been dozens of ports and clones created by developers all over the world. The list of original Doom source ports detailed below should provided you with enough information and details on how you can start to play the original Doom game for free on your Windows, Mac or Linux based PCs. For more information on the original Doom game form id Software, be sure to check out the Doom game page or pick up the conversation about Doom in our forums.
The list of free Doom downloads below are only a few of the ports that have been made and are still available. These are also some of the most played and well coded with some being updated as recently as this year (2016). Be sure to check out the Doom download page for direct links to download each version.
- PrBoom – PrBoom is a Doom source port that has been developed for Linux, Windows and Mac PCs it fixes some of the bugs in the original Doom as well as has the option to have the graphics rendered in OpenGL. This port of the original Doom was actually used by id Software for their development if the iOS version of Doom.
- ZDoom – ZDoom ins a source port of the original Doom for Windows, Linux and Mac OS X based PCs, it is one of the most popular ports available and the one recommended to download. However the main port requires users to install their own resource file for the Doom game engine, these are the game files that include the graphics, sound and levels. Without an IWAD, Zdoom does not offer any game play. Fortunately there are more than a dozen IWAD files available that cover various versions of the original Doom as well as other Doom clones. Other game IWADs that are compatible with Zdoom are those of Doom II, Heretic, Hexen and more. A full list of IWAD files can be found on the official ZDoom website as well as installation instructions.
- GZDoom – GZDoom is a Doom port based on ZDoom that upgrades the version of OpenGL that is supported to OpenGL 3. GZDoom, like ZDoom is still actively being developed and updated.
- ZDaemon – ZDaemon is online multiplayer port of the original Doom. It allows players to connect to multiplayer servers and play against others online just like current multiplayer shooters such as games from the Battlefield and Call of Duty Series of games.