What is .DEM file extension?
.DEM file extension is a known file type. This section tells you everything you need to know about this extension.
Game replay file created by various first-person shooter games and most popularly by Counter-Strike (supported by Valve's Source game engine); saves a video recording from one player's perspective in a single or multiplayer game; used for sharing replays with others.
To play a Counter-Strike DEM file in Windows, first place it in the cstrike\ installation directory. Next, start Counter-Strike and open the console window. From the console window, type viewdemo demoname, where "demoname" is the filename without the ".dem" extension.
DEM files are also used by Hexen II, Quake, and Unreal Tournament. However, the files are only playable on the game for which the demo was created.
NOTE: DEM files created by Source engine games, such as Counter-Strike, can be opened in VirtualDub to play the video frame sequence and record it to other output formats, such as .AVI. There is a size limitation of 2 GB for AVI videos created by Valve's source engine. You can install the Apple QuickTime component to encode the .H264 codec in order to avoid the size limitation.
You can see a list of software programs below that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.