glTF vs FBX: Which 3D Format Should You Actually Use?

If you work with 3D at all — game assets, product renders, AR, architectural models — you eventually hit the glTF-versus-FBX fork, usually at the worst possible moment: export dialog open, deadline looming, and no idea which one won’t break on the other end. Both carry meshes, materials and animation. Both are everywhere. But they were designed for different worlds, and picking the wrong one costs you broken materials, bloated files, or an afternoon of re-exporting. Here’s the honest comparison, with a clear rule you can actually remember.

The one-sentence answer

If your model is headed for the web, a browser, AR, or any modern real-time viewer, export glTF/GLB. If it’s moving between Autodesk-heavy desktop tools — Maya, 3ds Max, MotionBuilder — or into an animation pipeline with complex rigs, FBX is often the safer courier. Everything below is the reasoning behind that split, and the edge cases where it flips.

What each format actually is

FBX (Filmbox) was born in the late 1990s for motion-capture software, got bought by Autodesk in 2006, and became the de facto exchange format for the film and games industries. Its superpower is rich animation and rigging data: skeletons, skinning weights, blend shapes, multiple animation takes, cameras and lights. For two decades, “send me the FBX” has been how a rigged character travels between artists. Its catch is that it’s proprietary — Autodesk controls the spec, the internals have drifted across versions (FBX 2011 vs 2020 can behave differently), and materials in particular translate inconsistently between programs because every tool interprets FBX’s material model slightly differently.

glTF (GL Transmission Format) is much younger, published by the Khronos Group in 2015 and explicitly designed for one job: delivering 3D efficiently to real-time renderers, especially on the web. The nickname sticks because it’s accurate — glTF is “the JPEG of 3D.” It’s an open standard, it stores physically-based (PBR) materials that look consistent across viewers, it supports skeletal and morph animation, and crucially it supports Draco and meshopt compression that can shrink geometry by 80–90%. Its binary flavour, GLB, packs geometry, textures and everything else into a single self-contained file.

That origin story explains almost every practical difference between them.

Materials: where the biggest surprises live

This is the category that ruins the most afternoons, so start here. glTF uses a single, standardised PBR material model (metallic-roughness). Because the spec is precise about how materials behave, a glTF that looks right in one viewer looks right in the next — Blender, our browser 3D viewer, a game engine, an AR headset. There’s very little “it looked fine on my machine” with glTF materials.

FBX, by contrast, has no single agreed material model. It can carry Phong, Lambert and various Autodesk-specific shaders, and when a file crosses from Maya to Blender to Unity, each program does its best to reinterpret them — which frequently means textures that detach, colours that shift, or a model that arrives an unhelpful flat grey. FBX is genuinely excellent at carrying geometry and animation between tools; it’s the materials that need babysitting. A common professional workflow is to move geometry and rigs via FBX but re-author or re-link materials on the receiving end rather than trusting them to survive the trip.

The takeaway: if consistent, correct materials matter and the destination supports it, glTF removes an entire class of problems.

File size and loading speed

For anything that has to download — a web page, an AR experience, an app — size is a feature, and glTF wins decisively. A GLB with Draco compression is routinely a fraction of the equivalent FBX. It’s not unusual to see a model that’s 40 MB as FBX come in under 5 MB as a Draco-compressed GLB with no visible quality loss. That’s the difference between a product viewer that loads instantly and one that spins for ten seconds and loses the visitor.

FBX carries no comparable built-in geometry compression, and its files skew larger because they store more (and more redundant) data. For desktop-to-desktop transfer over a fast local network, nobody notices. For delivery to a user’s phone over mobile data, it’s the whole ballgame. If your model’s journey ends at a download, glTF is almost always the right answer — and our guide to reducing 3D file size goes deep on the compression settings that make the gap so large.

Animation and rigging

Here’s where FBX earns its keep. Both formats support skeletal animation and morph targets, but FBX has two decades of battle-testing with complex character rigs — constraints, multiple animation takes bundled in one file, custom attributes, facial rigs — and Autodesk tooling round-trips its own FBX reliably. If you’re passing a fully rigged character between Maya and MotionBuilder, or handing animation to a studio that lives in 3ds Max, FBX is the format they expect and the one least likely to lose a constraint in translation.

glTF handles animation well for delivery — a walk cycle, a rotating product, morph-based expressions all play back perfectly, and you can scrub them in most viewers including ours. What it’s not designed for is being an intermediate working format for heavy rig authoring; it deliberately bakes things down for efficient playback rather than preserving every authoring nuance. So: FBX for authoring and exchanging complex animation between DCC tools; glTF for shipping animation to a viewer or engine.

The head-to-head table

	glTF / GLB	FBX
Origin	Open (Khronos), 2015	Proprietary (Autodesk)
Built for	Real-time delivery, web, AR	DCC-to-DCC exchange, animation
Materials	Standard PBR, consistent	Variable, translate inconsistently
Compression	Draco / meshopt (huge)	None built-in
File size	Small	Larger
Complex rigs	Good for playback	Best-in-class exchange
Self-contained	GLB packs everything	Usually references textures
Web support	Native	Needs conversion

Choosing in real situations

Building a web product configurator or AR viewer? glTF/GLB, no hesitation — it’s the native format of the web and it’ll be smaller and more consistent. Preview the export in our browser 3D viewer before you ship it; if it looks right there, it’ll look right for your users, because the viewer uses the same WebGL pipeline your visitors will.

Handing a rigged character to an animation studio? Ask what they use. If it’s Autodesk tooling, FBX is what they expect and what preserves the rig. Don’t fight the pipeline.

Sharing a model with someone and unsure what they can open? GLB, because it’s self-contained (one file, no missing textures) and opens in the widest range of free tools, including any browser via our viewer — the reasoning is laid out in the 3D file formats guide.

Exporting from Blender for the web? glTF, and there are specific settings that make the difference between a clean export and a broken one — we cover them in exporting from Blender for the web.

Archiving a finished asset? A slightly contrarian tip: keep the source file (the .blend, .max, whatever made it) as your true archive, and treat both glTF and FBX as disposable exports you can regenerate. Neither interchange format preserves everything your authoring tool knows.

The mistake almost everyone makes once

The classic error is treating these as interchangeable and exporting whichever the dialog defaulted to. You send an FBX to a web developer who spends a day converting it and fixing materials; or you export glTF from a rigging tool and watch a constraint vanish. Both are avoidable by asking one question before you export: where does this file end up? A browser or engine or phone → glTF. Another Autodesk desktop tool or a heavy animation pipeline → FBX. That single question resolves the fork correctly the vast majority of the time.

What about OBJ, STL and the others?

Worth a one-paragraph aside, because people often reach for glTF or FBX when something simpler fits. If your model is static geometry with no animation and you just need maximum compatibility, OBJ still works everywhere. If it’s headed to a 3D printer, you want STL or 3MF, not either format in this article. glTF and FBX are the right debate specifically when you have materials and/or animation to preserve. The full landscape — which format stores what, and why .blend and .uasset can’t be opened directly — is covered in the complete formats guide.

Converting between them (and why you sometimes must)

Real pipelines aren’t pure. You’ll regularly receive an FBX and need a GLB for the web, or vice versa, and knowing how to convert cleanly saves the “re-export from source” scramble. The reliable path is a dedicated conversion tool rather than a chain of imports: command-line utilities like FBX2glTF (Facebook’s converter) or the broader gltf-transform toolkit handle FBX-to-glTF well, preserving geometry and animation while translating the material model. Blender itself is a capable free converter — import the FBX, then export glTF — and it’s often the most forgiving option because it re-interprets the materials into its Principled BSDF on the way in, which then maps cleanly to glTF’s PBR on the way out.

The one thing to watch in any conversion is, predictably, materials. FBX-to-glTF conversions frequently need a material pass afterward, because FBX’s ambiguous material data doesn’t always survive the translation to glTF’s strict PBR model intact. Convert, then open the result in a viewer and check every material before trusting it. Geometry and animation almost always convert faithfully; it’s the surface appearance that occasionally needs a human eye. And whichever direction you convert, remember the golden rule from earlier: if you still have the original source file (.blend, .max), regenerating a clean export from it usually beats converting a lossy intermediate.

Where USD fits in

A fair question in 2026: what about USD (Universal Scene Description), the Pixar-born format that’s increasingly central to large studio pipelines and Apple’s AR ecosystem (as USDZ)? USD is genuinely powerful for composing large scenes — layering, referencing and non-destructively assembling complex environments across teams — which is a different job from either glTF or FBX. For a single asset headed to a web page, glTF remains simpler and better-supported. For Apple’s AR Quick Look specifically, USDZ is the required format. USD isn’t a replacement for the glTF-vs-FBX decision so much as a third tool for a third problem (scene assembly at scale); for the everyday “export one model to the web” task this article is about, glTF is still the answer. The full format landscape, including which files can’t be opened directly at all, is mapped in the 3D formats guide.

Quick answers

Is glTF better than FBX? For the web, AR and real-time delivery, yes — it’s smaller, its materials are more consistent, and browsers read it natively. For exchanging complex rigs between Autodesk desktop tools, FBX is often better. “Better” depends entirely on the destination.

Can I convert FBX to glTF for free? Yes — import the FBX into Blender and export glTF, or use the free FBX2glTF / gltf-transform command-line tools. Check materials afterward in a viewer, since FBX material data doesn’t always survive translation.

Does FBX support PBR materials? Not natively or consistently — FBX predates the PBR standard and each program interprets its materials differently, which is why they translate unreliably. glTF was built around PBR, so its materials look the same everywhere.

Which is smaller? glTF/GLB with Draco compression, by a wide margin — often a fraction of the equivalent FBX. See reducing 3D file size for why.

Bottom line

glTF and FBX aren’t rivals so much as specialists. FBX is the seasoned courier for complex animation moving between professional desktop tools; glTF is the efficient, consistent, web-native format for delivering finished 3D to viewers, browsers and real-time engines. Ask where the file is going, pick accordingly, and — whichever you choose — drop the result into a viewer before you send it, so “it looked fine on my machine” never becomes someone else’s problem.