MDC Converter
FileFlip converts MDC files into 14 other formats entirely inside your browser, using Assimp compiled to WebAssembly. The MDC file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert an MDC file?#
- Drop your MDC file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert MDC files online?#
Yes, because nothing is uploaded. FileFlip converts MDC files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What happens to a MDC file#
FileFlip converts MDC into 14 formats with Assimp, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | 3D Models |
|---|---|
| File extension | .mdc |
| FileFlip support | Read only, so it is a source rather than a target |
| Conversions available | 14 |
| Engines | Assimp |
| Downloaded to your browser | 11.2 MB on the first conversion, then cached |
What is an MDC file?#
An MDC file is Return to Castle Wolfenstein's compressed variant of id Software's MD3 model format, storing most animation frames as small per-vertex byte deltas from a full base frame instead of complete positions for every frame.
Use MDC only when working directly inside Return to Castle Wolfenstein's modding pipeline, where the smaller animation footprint is the point.
Convert MDC to a modern interchange format when the model needs to leave that specific engine, since almost nothing outside its immediate tool ecosystem reads MDC.
The MDC file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
MDC questions people ask#
What is an MDC file?
An MDC file is a model in the compressed variant of MD3 built for Return to Castle Wolfenstein in 2001, storing most of its animation frames as small per-vertex deltas from a base frame rather than full positions for every frame.
How is MDC different from MD3?
MDC keeps MD3's structure, including the head, torso and legs split and tag-based attachment points, but compresses most frames down to per-vertex byte offsets from a base frame instead of storing complete vertex positions in every frame. That trades a small amount of precision for meaningfully smaller animation data.
What still opens MDC files?
The open-source iortcw engine, a modernized rebuild of Return to Castle Wolfenstein's engine, loads MDC files from the original game data. General-purpose viewers like Noesis also read MDC for inspection or conversion outside the game.