VMF File

What are VMF files and how to open them

Are you having problems opening a VMF 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 VMF files.

What is a VMF file?

VMF files have multiple uses, and Covox Speech Thing Audio Sample is one of them. Read more about the other uses further down the page.

Covox Speech Thing Audio Sample

We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

How to open VMF files

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

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

Last updated: August 14, 2026

All known file formats using extension .VMF

While Covox Speech Thing Audio Sample is a popular type of VMF-file, we know of 4 different uses of the .VMF file extension. Different software may use files with the same extension for different types of data.

GFX9000 Movie Format

We know that one VMF format is GFX9000 Movie Format. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

Valve Map Format

Valve Map Format files store the editable source for 3D maps used in Valve's Hammer map editor for the GoldSrc and Source game engines. They are human-readable plain text files that map designers use to build levels by defining geometry ("brushes"), entities (interactive or static objects), textures, lighting, world boundaries, cameras, view settings, and editor-only metadata. These files are never directly used by the game engine; instead they must be compiled into a ".BSP" format before being loaded in-game.

Maps created in Hammer (version 4.0 and later) produce the VMF file. Users open and modify its contents using Hammer or compatible tools, adjusting layout, textures, entity placements, lighting parameters, etc., until the design is final. Then Hammer's build tools convert or "compile" the VMF into executable map files (BSP plus associated resources) that the game engine can render and run. VMF serves as a design-first format, ideal for editing and version control because it is easy to read and diff.

Internally VMF uses a structured, bracketed text format sometimes called KeyValues. It starts with a "versioninfo" section declaring editor version, mapversion, formatversion and whether the file is a prefab. Other sections include "world" or "worldspawn" for geometry and global settings; "entity" sections for objects; "visgroups", "viewsettings", "cameras", "cordon" and "hidden" for editor structure and organisation. Identifying byte-patterns include the ASCII string "versioninfo" at byte offset 0, and keywords like WORLDSPAWN, ENTITY, MATERIAL, PLANE, SOLID, LIGHTMAPSCALE, CLASSNAME, etc.

VMF opener for Windows

We have identified one VMF opener that is compatible with this specific type of VMF file.

VocalTec Media File

We know that one VMF format is VocalTec Media File. 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 VMF files. Remember, different programs may use VMF files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about VMF file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.