9 file types use the .cfg file extension.

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What is a CFG file?

A CFG file is a generic preference file that stores settings and configuration information. It is used by various programs, which means different CFG files may store data in different formats. CFG files typically should not be opened manually but may be saved in a text format that can be viewed in a text editor.

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Category: Settings Files

Celestia Configuration File

Celestia.cfg is a configuration file used by Celestia, a 3D space simulator. It is a plain text file that specifies the databases, scripts, images, and other files Celestia loads at startup. Windows users can edit their CFG file's settings with Celestia Config Manager.

Celestia is a free, multiplatform program that allows users to explore a 3D simulation of outer space. Optionally, users can modify a variety of Celestia's settings, such as:

These settings (and several others) are all defined in Celestia's celestia.cfg file.

celestia.cfg - The name of Celestia's configuration file.

Windows users can open and edit celestia.cfg with Celestia Config Manager, a program designed specifically to allow Celestia users to manage their settings. Other users who want to open and edit celestia.cfg can do so with any text editor. Note, however, that editing celestia.cfg improperly can cause Celestia to function incorrectly.

Programs that open or reference CFG files

Updated: December 6, 2023

Cal3D Model Configuration File

Three-dimensional model configuration file used by Cal3D, an open source character animation toolkit; saved in a plain text format and contains references to model components; used for putting all model components together.

CFG files contain references to Cal3D skeleton files ( .CSF or .XSF extension), animation files ( .CAF or .XAF extension), meshes ( .CMF or .XMF files), and materials ( .CRF or .XRF files). They also store the root directory for the referenced files and the model scale.

Programs that open CFG files

Updated: July 6, 2017

MAME Configuration File

XML keyboard configuration file used by MAME arcade video game emulators; contains keyboard mappings and hotkeys used for playing a game; used for configuring keyboard controls based on the player's preferences.

Separate CFG files can be saved for different games. This gives players the ability to customize controls separately depending on the game being played.

Programs that open or reference CFG files

Updated: November 16, 2010

LightWave Configuration File

Preferences file created by LightWave 3D, a modeling and rendering application for still frames and animation sequences; saves various application configuration options; used for remembering presets for the user.

Programs that open or reference CFG files

Updated: May 17, 2011

Wesnoth Markup Language File

Game file used by The Battle for Wesnoth, a free turn-based strategy game for Mac, Windows, and Linux; contains source code written in the Wesnoth Markup Language (WML), a proprietary language used for creating scenarios, campaigns, units, and other game content for The Battle for Wesnoth.

CFG files can be edited using any text editor. Some WML syntax highlighting plugins have been developed for text editors such as Emacs and Vi.

Programs that open or reference CFG files

Updated: March 22, 2011

Citrix Server Connection File

Contains connection information for connecting to a Citrix server; may include hostname, IP address, server port, username, password, etc; multiple CFG files may be used by Citrix client software to connect to various servers.

Programs that open or reference CFG files

Updated: April 30, 2007

Source Engine Configuration File

A CFG file may also be a configuration file used by a Valve Source Engine video game, such as Half-Life 2. It contains a newline-delimited list of plain text commands that modify a game's settings. Players can execute the commands a CFG file contains manually, via a game's Developer Console, or automatically, by placing them in an appropriate game directory.

Source is a 3D game engine that Valve used to develop Half-Life 2, Garry's Mod, Team Fortress 2, Portal, and many other games. Games developed using the Source engine use a variety of CFG configuration files to load data and set certain game settings.

While most players will never need to open or edit a CFG file, game modders sometimes create and use their own, custom CFG files. They then execute the commands these files contain by either:

For example, a modder may place a modsettings.cfg file in a game's mod directory and use it to load a game mod. Or, a modder may replace a game's autoexec.cfg file with a customized version of that file, used to modify the game's gameplay (for example, by enabling cheats).

autoexec.cfg - Contains commands run at game startup.

modsettings.cfg - Contains commands used to load and apply game mods.

You can open a CFG file and edit the commands it contains with Microsoft Visual Studio Code or any other text editor.

Programs that open or reference CFG files

Updated: June 22, 2023

M.U.G.E.N Configuration File

A CFG file may also be a configuration file used by M.U.G.E.N, a free sprite-based game engine used to create 2D fighting games. It contains settings that control a fighting game's gameplay, sounds, and appearance. CFG files used with M.U.G.E.N are typically named mugen.cfg .

A M.U.G.E.N CFG file allows fighting game creators to modify their game's basic rules, including round time, game difficulty, game speed, combo damage multipliers, and more. It also allows creators to choose what resolution M.U.G.E.N shows their game at, as well as whether M.U.G.E.N should play sound effects and music. Advanced M.U.G.E.N users can customize a number of additional game-related settings using a CFG file.

M.U.G.E.N's default CFG file, mugen.cfg , is stored in the program's data folder. While you can edit game settings directly within mugen.cfg , it's recommended that you create a copy of the file before editing it, so you can easily revert M.U.G.E.N to its original settings if necessary.

mugen.cfg - The default configuration file included with M.U.G.E.N. It is located in the program's data folder.

Because they are plain text documents, you can open mugen.cfg or any other M.U.G.E.N CFG file with any text editor. In Windows, you can open a CFG file with Microsoft Notepad or Microsoft WordPad . In macOS, you can use Apple TextEdit .

Programs that open or reference CFG files

Updated: August 20, 2020