PMX to X3D Converter
FileFlip converts PMX to X3D 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 a PMX file to X3D?#
- Drop your PMX 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 X3D 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 X3D file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting PMX to X3D lose quality?#
Not in the sense of pixels or samples. Converting PMX to X3D rebuilds the file in X3D's own model rather than re-encoding it, so everything X3D 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 PMX files online?#
Yes, because nothing is uploaded. FileFlip converts PMX 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 PMX to X3D actually does to the file#
Converting PMX to X3D 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: PMX → X3D |
| 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 a PMX file?#
A PMX file is a binary character model for MikuMikuDance, the successor to the older PMD format, built by Yu Higuchi's tools to hold a mesh alongside its bones, facial morphs and rigid-body physics as one package that MMD loads and animates directly.
Use PMX when a character needs to be posed, animated or physics-simulated inside MikuMikuDance or the wider MMD tool ecosystem.
Convert PMX to glTF or FBX when an MMD character needs to move into a game engine or renderer outside the MMD ecosystem.
What is an X3D file?#
An X3D file holds a 3D scene in the XML encoding of the ISO X3D standard, describing geometry, materials, animation and interactive behaviour for playback in a compliant browser or viewer.
Use X3D for scenes that need standards-track archival stability, or when a project already runs on X3D-based simulation or visualisation tools.
Convert X3D to glTF or GLB for anything shipping to a modern web page, game engine or AR viewer.
PMX to X3D questions people ask#
What is a PMX file?
A PMX file is a MikuMikuDance character model, storing a mesh together with its bones, facial morphs and rigid-body physics in one binary file. It's the successor to the older PMD format and the format almost all current MMD character content is distributed in.
What's the difference between PMD and PMX?
PMD is the older MikuMikuDance model format, and PMX succeeded it with a more flexible bone and morph system, support for more materials, and additional physics options. PMX Editor can open and convert PMD files, and current MMD content is essentially all PMX now.
Can I open a PMX file outside MikuMikuDance?
Yes, Blender opens PMX files through the community mmd_tools add-on, which reads the mesh, bones, morphs and physics much the way MikuMikuDance does. Outside of MMD-focused tools, native PMX support is rare.
What replaced VRML?
X3D replaced VRML, carrying the same kind of web-delivered interactive 3D scene forward as an ISO standard first approved in 2004, with an XML-based encoding in place of VRML's plain-text syntax.