File with .DNF extension contains level map data for Duke Nukem Forever computer game. File includes information such as terrain layout, buildings and object, spawn points, weapon and ammo locations.

DNF map files are used for generating level data in single- and multi-pilayer game modes. Duke Nukem Forever is a sequel to cult-classic shoot’em up game Duke Nukem 3D, released in 1996. Custom-made DNF files can be downloaded from the internet.