.CHD File Extension
File TypeMAME Hard Disk Image
What is a CHD file?
Arcade game disk image used by some MAME (Multiple Arcade Machine Emulator) emulator games; stores a compressed version of the entire contents of an arcade machine's hard disk; used in conjunction with a game ROM to load the game.
To load a MAME arcade game, you typically need to place the CHD file in a directory has the same name as the ROM's filename prefix (some emulators use a single generic directory for all CHD files). For example, for a ROM with the filename mygame.zip, a CHD file named mygame.chd, and a ROM directory Roms, emulators commonly use the following convention: