DG File

What are DG files and how to open them

Are you having problems opening a DG file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your DG files.

What is a DG file?

A .DG file is a Dialog Source Code file.

Dialog Source Code is the human-readable source writing for the Dialog programming language by Linus Åkesson, used to build interactive fiction stories. It includes definitions of scenes, rooms, objects, player actions, and story metadata. Authors write this source in plain text with Dialog's syntax to capture narrative content, game logic, input grammar, and world state. After editing, the tool dialogc (the Dialog compiler) takes this source and compiles it into a story file in a runtime format such as Z-code or the Å-machine format.

Dialog source code is structured into rule definitions using predicates. Typical parts include metadata rules like (story author), (story title), (story release $N), and details about rooms, objects, traits, dynamic flags, grammar for player input, and the "intro" predicate for startup behaviour. The standard library provides many built-in predicates and conventions for naming to simplify authoring.

Internal identifiers help tools detect this format by looking for signature strings at the start or within the file. These include strings like (storytitle) at offset zero, or labels like (STORY AUTHOR), (STORY RELEASE), (ROOM *), (INTRO). These elements, along with the specific syntax of Dialog - such as predicates in parentheses, # for objects, $ for variables, etc. - are characteristic.

How to open DG files

Important: Different programs may use files with the DG file extension for different purposes, so unless you are sure which format your DG file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested four different DG openers which you will find listed below.

Last updated: October 27, 2026

Various apps that use files with this extension

These apps are known to open certain types of DG files. Remember, different programs may use DG files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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