FBX File Format (.fbx)

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.

.fbx3D Models

FBX at a glance#

Full name	Autodesk Filmbox
File extension	.fbx
Category	3D Models
Developer	Autodesk
First released	1996
Compression	Uncompressed
FileFlip support	FileFlip reads and writes this format

What a .fbx file can hold#

These are the things a FBX file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.

Textures and materials	Yes
Skeletons and animation	Yes

Strengths and limitations of FBX#

What FBX does well

Carries a full scene, meshes, materials, skeletons, skinning and animation, in one file
The format almost every game engine and DCC tool targets first for pipeline interchange
Both a compact binary variant and a readable ASCII variant exist

Where FBX falls short

Proprietary and versioned with no official public specification, so third-party writers rely on reverse-engineered documentation
A file exported from one application's FBX writer sometimes fails to import cleanly into another's
Autodesk has shipped many incompatible FBX SDK versions over the years, so an old FBX can trip up a newer importer and vice versa

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.

How to open a .fbx file#

A .fbx file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts FBX into a format your machine already opens, and it does it in the browser tab rather than on a server.

Platform	Programs that open it
Windows	Autodesk Maya, 3ds Max, Blender, Unity, Unreal Engine
macOS	Blender, Autodesk Maya, Cinema 4D
Linux	Blender
Web	FileFlip

FBX 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.

Converting FBX files#

Convert FBX to another format

Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.