D File

What are D files and how to open them

Are you having problems opening a D 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 D files.

What is a D file?

D files have multiple uses, and D Source Code is one of them. Read more about the other uses further down the page.

D Source Code File

The .d file extension is most commonly used for program files that have been written in the D programming language. The D programming language is similar to the C++ programing language but combines C++ with the power of other modern programming languages like Python and Ruby. Programmers can compile the D files into an executable computer application by utilizing a D compiler.

How to open D files

We have identified three D openers that are compatible with this specific type of D file.

Programs that open D Source Code files

Last updated: September 21, 2026

All known file formats using extension .D

While D Source Code File is a popular type of D-file, we know of 9 different uses of the .D file extension. Different software may use files with the same extension for different types of data.

CHEMVIEW Animation Data File

We know that one D format is CHEMVIEW Animation Data File. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

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

DVC Database

We know that one D format is DVC Database. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

GBG DraftMaker Drawing

Caneco BT project files store the electrical installation a designer has laid out in Caneco BT.

GBG DraftMaker Drawing format stores technical 2D drawings created with GBG DraftMaker (later versions known simply as GBG, now by company think3). It was introduced in version 4.0 and continues through version 9.1. It is designed to store full CAD-style drawings - including geometry, dimensioning, layers, text annotations - and is used for creating precise technical plans.

These files are produced exclusively by GBG DraftMaker software. Rendering and printing can also be done via associated tools such as GBPLO ("Plot") from think3, which accepts these drawing-format files as input along with AutoCAD DXF and DWG formats.

Files begin with a distinctive ASCII header signature starting at offset 0: the bytes read "}9GBG-V{6.{0{0;GBLIB-V{6.{0{".

Infinity Engine WeiDU Dialogue

Infinity Engine WeiDU Dialogue files are plain-text files used by the WeiDU tool to define or modify dialogues in games that use the Infinity Engine. They allow modders to create new conversations or patch existing dialogue definitions (DLG files) using human-readable syntax. Dialogue states, replies, conditional triggers, and transitions are expressed symbolically, optionally translated for different languages, which facilitates mod compatibility and localization.

These files are written and edited by mod authors using WeiDU. WeiDU reads them when installing mods to produce or adjust the compiled binary dialogue resources the game engine uses. Typical operations include creating brand new full dialogue sets (BEGIN ... state blocks), inserting or extending transitions in states, replacing specific states, adding triggers or replies, and handling speaker text with translation support.

Dialogue state labels can be numeric (matching existing game state IDs) or symbolic names defined in the D file; only WeiDU's D file format allows symbolic labels. States include conditional IF triggers to determine when they appear, SAY text for the non-player character's line, and transition entries which may provide replies for the player, actions, journal entries, or transfers to other states or dialogue files. The engine selects among states based on these triggers and optional weights.

Files begin with a BEGIN action (which specifies the dialogue filename and optional flags), followed by a structured list of states. Each state starts with something like IF [ WEIGHT #n ] trigger THEN BEGIN label SAY text transition-list END. Transitions are defined with IF transTriggerStrings, optional REPLY texts, actions (DO), movement to other states or files (GOTO, EXTERN, EXIT), and other features.

Internal signatures include the ASCII signature BEGIN~ at offset zero, or the string BEGIN ~ somewhere in the file.

PADS Parts Library PCB Decals

PADS Parts Library PCB Decals store electronic footprint (decal) definitions in plain text. These files are created by Mentor Graphics PADS Layout's library manager when the PCB Decals section of a library is exported in ASCII format. They describe how pads, terminals, text, and graphics combine to form physical component footprints for printed circuit board layouts.

These files are used to share or migrate PCB footprint data between PADS and other tools. For example, exporting the PCB Decals library to a .D ASCII file allows Altium Designer or other EDA tools to import the same footprint data as a PCB library. The .D ASCII format corresponds to PADS's internal binary decal library (usually .pd9) when saved in readable form.

Inside a PCB Decals ASCII file the structure begins with a control statement like PADS-LIBRARY-PCB-DECALS-V9 marking the start, followed by a header that names each decal, specifies the units (imperial or metric), origin location, number of attributes, number of drawing pieces, terminals, pad stacks, and maximum layers. Then there are definitions of: attributes (name/value pairs), label placement (text for reference designator, part type, extra attributes), piece definitions (lines, copper shapes, cutouts), terminal definitions (pin positions, rotations, mirror flags), and pad-stack definitions (shape, drill, plating). The file ends with END.

Technically the file's first line must be the control statement beginning and ending with asterisks. That header includes "PADS-LIBRARY-PCB-DECALS-V9" or similar, where "V9" is the version number. Units types are indicated (I for Imperial, M for Metric), coordinates are given in either mils or millimeters. Pieces use keywords like OPEN, CLOSED, CIRCLE; terminals start with "T" lines; pad stacks begin with "PAD" headers.

Painter 3D Model

Painter 3D Model files store three-dimensional object data in plaintext form. These files describe a geometry by listing components such as faces, vertices, ambient lighting, shading, and colour sources so that a simple 3D modelling or rendering program can load and display the shape. The format is intended for small-scale 3D objects or models requiring basic lighting and vertex/face definitions rather than advanced rendering features.

These files are created and edited with applications that support the "Painter 3D Model" format. Once written, they are used by the same or compatible 3D tools to display, manipulate, or export the object's geometry, colours, lighting settings, and texture palette information. They are rarely used for animation or complex geometry, but more often for static models, texture-mapping, and preview rendering workflows.

Internal components include a palette of colours, named objects or shapes, lists of vertices with their positions, definitions of faces (which vertices make each face), and possibly lighting and shading parameters (ambient light, reflections or sources of light). The file often contains keywords such as VERTICES, FACES, SHADING, SOURCES, AMBIENT, PALETTE, and SHAPE. The file usually begins with a line "Palette:" at byte offset zero. It may also include colour values (RCOLOR), saturation levels, object definitions, and an indication of how each face should be shaded.

SPPACK Sampled Audio File

We know that one D format is SPPACK Sampled Audio File. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

Steinberg Studio Module Driver

We know that one D format is Steinberg Studio Module Driver. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

Various apps that use files with this extension

These apps are known to open certain types of D files. Remember, different programs may use D 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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