Unreal 3 game data package
File type: Game file
A UPK file is a game data package used by Unreal Engine 3 games, including Unreal Tournament 3.
It stores resources that the game loads during play.
File type category:
Game file
Date updated: October 17, 2026
The UPK file extension is associated with Unreal Engine 3, a video game engine developed by Epic Games. It is used by games such as Gears of War and Mass Effect, as well as by other Unreal Engine 3 titles.
A UPK file is a package containing game resources and related object data. Depending on the game, it can contain textures, text, sounds, maps, meshes, materials, animation and other assets used by the game.
The Unreal Development Kit and the Unreal Engine 3 games associated with this extension are available for Microsoft Windows. UPK is a proprietary, game-specific package format, and its contents and compatibility can vary between titles. It is mainly encountered in older Unreal Engine 3 games and is not a general-purpose archive format.
On Microsoft Windows, open a UPK file with the Unreal Development Kit when the package is compatible with that development kit. The game that created the file can also load it as part of its own data, but commercial game packages may not open correctly in UDK because of differences between games and engine versions.
A UPK file cannot usually be converted directly to another general-purpose format. If the package is compatible with the Unreal Development Kit, individual assets such as textures, meshes or sounds may be exported and then converted separately; this does not produce an equivalent converted game package.
Software applications that can open upk files:
Microsoft Windows
Software applications that can edit upk files:
Microsoft Windows
Software capable of saving upk files:
Microsoft Windows
Software apps that create upk files:
Microsoft Windows
Software applications that handle other tasks involving upk files:
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