ChessMaster saved game
File type: Game file
The cmg file extension is used by ChessMaster, a chess game for Microsoft Windows.
A cmg file stores a saved chess game position and the state of a game in progress.
Found 2 different file type records with the same cmg filename suffix.
File type category:
Game file
Date updated: October 22, 2026
The cmg file extension is associated with ChessMaster, an older chess computer game for Microsoft Windows developed and sold by Ubisoft.
A cmg file contains saved chess game data, allowing a game in progress to be opened and continued in ChessMaster. It is a legacy format associated with older Windows versions of the software.
On Microsoft Windows, open the compatible version of ChessMaster and use its Load Game option to select the .cmg file.
Open the file in a compatible version of ChessMaster; any export to another chess-game format depends on the features provided by that version.
Software applications that handle other tasks involving cmg files:
Microsoft Windows
File type category:
System file
Date updated: October 19, 2026
cramfs is a Linux file system designed to be simple, small, and efficient to compress. A cmg file contains a read-only file system image and the files stored within it.
Embedded Linux systems and other small devices can use the image as part of their system software. It is normally mounted or unpacked by Linux file system tools rather than opened as a regular document or archive.
On Linux or another Unix-like system, a cmg file can be opened with cramfs-aware file system tools. If it is a valid cramfs image, it can usually be mounted read-only through a loop device, or its contents can be extracted with suitable cramfs utilities.
These operations may require administrator privileges. A general-purpose archive utility or text editor will not normally open the file correctly.
A cmg file is a file system image, not a document format, so it normally has no useful direct conversion.
On Linux, its contents can be extracted and then used to build another cramfs image with the appropriate cramfs creation tools. To use a different file system format, extract the contents and create a new image in that format.
Software applications that handle other tasks involving cmg files:
Linux/Unix
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