glTF vs FBX vs OBJ: Which 3D Format for Game Dev?
May 27, 2026 · 3 min read · Written by the Grab3D team (About us)
Every 3D marketplace offers a soup of file formats, and picking wrong costs you an afternoon of debugging flipped axes and missing materials. Here is the short, practical version.
The one-paragraph answer
Use glTF/GLB where your toolchain reads it well: Godot, Blender and the web read it natively, Unity via a package, and Unreal Engine 5 ships a built-in glTF importer. Use FBX when your engine or workflow is built around it. Unreal projects and animation exchange between DCC tools are the classic cases. Treat OBJ as the universal emergency format: it always opens, but carries the least information.
glTF: the modern default
Designed by Khronos as a transmission format: compact binary (GLB), PBR materials included, meters/Y-up by definition, loads fast without conversion.
Strengths: open standard, no proprietary SDK, embedded textures, skinning and animation support, compact files, and optional extensions such as Draco mesh compression. The whole “web 3D” ecosystem (including the viewer on this site) runs on it.
Weaknesses: DCC tools historically preferred FBX, and not every importer supports every extension. Draco-compressed files are the most common stumbling block (see below).
FBX: the industry veteran
Autodesk’s proprietary workhorse. Still the safest bet for rigs and animation exchange between DCC tools and engines.
Strengths: mature animation pipeline, universal DCC and engine support. Weaknesses: closed format, version chaos (ASCII vs binary, many SDK versions), unit/axis conventions differ per exporter. The classic “my model is 100× too big and lying on its face” experience usually comes from FBX. Files are also larger: our FBX downloads are a median 1.7 times the size of the same model’s GLB.
OBJ: the survivor from the 1980s
Plain text, geometry only (plus basic materials via MTL). No rig, no animation, no scene graph, no units.
Strengths: practically everything opens it. Weaknesses: no scale convention (is 1 unit a meter? an inch? nobody knows), large uncompressed text files, and textures travel as separate image files next to an MTL. Use it when nothing else works. That is why we ship it as the fallback, zipped together with its MTL and textures.
What Grab3D gives you
You don’t have to pick just one. Every Grab3D model comes as GLB (textures embedded, meters, Y-up), FBX, a native .blend file, USDZ for Apple’s AR Quick Look and OBJ as a ZIP with MTL and textures. All of them use real-world scale, with the pivot at the base.
Two details worth knowing:
- No Draco in the downloads: our GLBs, including High Detail models and rigged characters, use no Draco mesh compression. That keeps them compatible everywhere: Godot imports them natively, Unity needs only glTFast or UnityGLTF (no
com.unity.cloud.draco), and Blender, Unreal Engine 5 and three.js read them without a decoder. Only the 3D preview on our website is Draco-compressed so it loads fast. If you want smaller files, compress a copy yourself, for example with gltf-transform. For Unreal Engine we still recommend the FBX as the most established route. - Rigs: rigged characters ship their walk and run clips in the GLB, FBX and .blend of the rigged variant. The rigged character guide walks through Unity, Godot and Unreal.
How big is each format in practice? We measured every download package in the library: GLB vs FBX vs USDZ vs OBJ vs BLEND file sizes. Each model page also lists exactly which files you get and how big they are.
Want the deep dive per engine? Read the Unity import guide or the Godot import guide.
