FBX to glTF Converter
FileFlip converts FBX to glTF 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 FBX file to glTF?#
- Drop your FBX 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 glTF 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 glTF file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting FBX to glTF lose quality?#
Not in the sense of pixels or samples. Converting FBX to glTF rebuilds the file in glTF's own model rather than re-encoding it, so everything glTF 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 FBX files online?#
Yes, because nothing is uploaded. FileFlip converts FBX 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 FBX to glTF actually does to the file#
Converting FBX to glTF 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: FBX → glTF |
| 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, or a ZIP when the source carries separate materials or buffers |
| 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. |
Worth knowing before you start:
- the result is a single file when the model has no external materials or buffers, and a ZIP when it does
What is an FBX file?#
An FBX file is Autodesk's proprietary binary or ASCII scene format, originally built by Kaydara for its Filmbox motion-capture software in 1996, that carries a full scene, meshes, materials, skeletons, skinning and animation together in one container.
Use FBX when a full rigged, animated scene needs to move between a DCC tool and a game engine, since almost every pipeline tool expects it.
Convert an FBX file when the destination needs an open, patent-unencumbered format, or when the application that wrote it isn't the one reading it and something is coming through wrong.
What is a glTF file?#
A glTF file is a JSON scene description, developed by the Khronos Group and first released in 2015, that lists a model's meshes, PBR materials, animations and scene hierarchy while its binary geometry and textures sit alongside it in separate buffer and image files.
Use glTF's JSON form when a pipeline needs to inspect or hand-edit the scene structure directly, since it's plain, indexed JSON.
Convert glTF to GLB when the model needs to travel or load as a single file instead of a folder of JSON, buffers and textures.
FBX to glTF questions people ask#
What software opens FBX files?
Blender, Autodesk Maya, 3ds Max, Unity and Unreal Engine all open FBX files, since it's the format most 3D and game pipelines use to move scenes between tools. Which application wrote the file matters more than which one is opening it, because FBX exporters don't all interpret the format identically.
Why won't my FBX file import correctly?
FBX has no official public specification and Autodesk has shipped many versions of the FBX SDK, so an importer's behaviour depends on which application and version wrote the file. The usual fix is finding out exactly which tool exported it and using a matching or newer FBX SDK version to read it back.
Is FBX free to use?
Autodesk provides the FBX SDK free of charge, which is why so many applications support reading and writing FBX despite the format itself being proprietary and closed. There's no licence fee, but there's also no independent specification a developer can implement without Autodesk's SDK.
What's the difference between binary and ASCII FBX?
Binary FBX is compact and is what most software writes by default, while ASCII FBX lays the same scene out as readable, tree-structured text. The ASCII form is useful for inspecting or debugging a file by hand, but it isn't used in ordinary pipelines because of its larger size.