MD3 to USDZ Converter
FileFlip converts MD3 to USDZ entirely inside your browser, using Assimp compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an MD3 file to USDZ?#
- Drop your MD3 file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to USDZ and the conversion starts on its own. FileFlip downloads 11.2 MB of WebAssembly the first time and nothing after that, then runs Assimp on your own machine.
- Save the USDZ file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting MD3 to USDZ lose quality?#
Not in the sense of pixels or samples. Converting MD3 to USDZ rebuilds the file in USDZ's own model rather than re-encoding it, so everything USDZ can represent comes through exactly and anything it cannot has to be dropped. Expect the geometry to be exact, and anything the target has no place for, such as a rig, to be left behind.
Is it safe to convert MD3 files online?#
Yes, because nothing is uploaded. FileFlip converts MD3 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 MD3 to USDZ actually does to the file#
Converting MD3 to USDZ runs on Assimp, downloads 11.2 MB of WebAssembly the first time and nothing after that, rebuilds the file in the target's own model.
| Engine | Assimp |
|---|---|
| Conversion path | One step: MD3 → USDZ |
| Downloaded to your browser | 11.2 MB, once, then cached by your browser |
| Quality | Rebuilt in the target's model |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Materials | Sometimes | Survives for some files and not others. |
| Textures | Sometimes | Survives for some files and not others. |
| Skeleton and animation | Sometimes | Survives for some files and not others. |
What is an MD3 file?#
An MD3 file is a Quake III Arena model, typically one piece of a character split into head, torso and legs that align through named tag points so the pieces can move and aim independently.
Use MD3 when authoring content for Quake III Arena or one of its still-active engine derivatives, since that ecosystem expects the head/torso/legs split.
Convert MD3 to a modern interchange format when the model needs to leave the Quake III engine family, since the three-piece split and tag system have no equivalent elsewhere.
What is a USDZ file?#
A USDZ file is a zero-compression ZIP archive holding one or more USD layers together with their textures, audio and other referenced assets, packaged as the single file Apple's AR Quick Look expects.
Use USDZ when a model needs to open in AR Quick Look on an iPhone or iPad, or travel as one self-contained file with its textures attached.
Convert away from USDZ when the model is headed into a DCC tool or pipeline that expects an unpacked USD layer rather than a zip package.
MD3 to USDZ questions people ask#
What is an MD3 file?
An MD3 file is id Software's model format for Quake III Arena, released in 1999, and it usually represents one part of a character, such as the head, torso or legs, joined to the others through tag points. Vertex-animated meshes replaced Quake II's single-piece MD2 models with this split so aiming and movement could animate separately.
Why is a Quake III character split into three files instead of one?
MD3 splits a player model into head, torso and legs so the torso and arms can aim independently of which way the legs are running or standing, a limitation of the whole-mesh vertex animation both MD2 and MD3 use. Tag points in each piece tell the engine exactly where to attach the next piece so the split is invisible during gameplay.
What opens MD3 files today?
The open-source ioquake3 engine and games built on it, like OpenArena, load MD3 files the same way the original Quake III Arena did. Standalone viewers such as Noesis and older editors like MilkShape 3D and QuArK also read MD3 for inspection or conversion outside the game.
What opens a USDZ file?
On a Mac or iPhone, USDZ opens straight in Quick Look from the Finder, Safari, Messages or Mail with no separate app needed. Blender and Adobe Aero also read USDZ on any platform if you need to edit rather than just view it.