What is a .fbx file?
Filmbox · 3D model · Autodesk · 2006
FBX is a rich 3D format used heavily in games and film. Beyond geometry it carries materials, textures, skeletons and animation, which makes it the go-to for moving fully rigged, animated characters between tools.
What is a .fbx file used for?
FBX bundles a complete 3D asset: meshes, materials, textures, bones, skinning and keyframe animation. That completeness is why game engines and film pipelines rely on it.
It is an Autodesk format, so support is strongest in Maya, 3ds Max, Blender and the major game engines.
FBX comes in two forms that hold the same scene: the usual binary version (which starts with 'Kaydara FBX') and an ASCII text version. It is also strongly tied to a version year, and the most common reason an FBX 'will not import' is a version mismatch between the exporting and importing tools.
The open glTF format is increasingly used for the same interchange role, especially on the web.
How to open a .fbx file
The .fbx format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .fbx file.
Windows
- Blender
- Autodesk FBX Review
- Unity
- 3ds Max
macOS
- Blender
- FBX Review
- Unity
Linux
- Blender
Web
- Some online 3D viewers
How to convert a .fbx file
You can convert a .fbx file to OBJ, GLTF, STL using a conversion tool or the export menu of an app that opens it.
.fbx file signature (magic bytes)
Programs recognise a .fbx file by the bytes at the start of the file, not by its name. These are the signatures for FBX. For a full breakdown, see the FBX file signature page.
| Hex signature | Offset | Note |
|---|---|---|
| 4B 61 79 64 61 72 61 20 46 42 58 | 0 | 'Kaydara FBX' (binary FBX) |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .fbx file?
FBX is a rich 3D format used heavily in games and film. Beyond geometry it carries materials, textures, skeletons and animation, which makes it the go-to for moving fully rigged, animated characters between tools.
How do I open an FBX file for free?
Blender opens and edits FBX for free. Autodesk's free FBX Review app previews them with animation.
Why won't my FBX import correctly?
Usually a version mismatch: FBX is versioned by year, and older software may reject a newer file. Re-export it to an earlier FBX version (2013 or 2014 are safe choices). Missing textures are a separate issue, FBX often references image files that must travel alongside it.
Related formats
Sources
Details on this page were checked against authoritative references: