Need help with glTFast?
Click the “chat” button below for chat support from the developer who created it, or find similar developers for support.

About the developer

294 Stars 57 Forks Apache License 2.0 791 Commits 47 Opened issues


glTF runtime loading and Editor import library for Unity

Services available


Need anything else?

Contributors list

# 87,346
708 commits
# 198,891
10 commits
# 114,811
5 commits
# 588,314
2 commits
# 279,889
1 commit
# 453,964
1 commit

glTFast 🚀

openupm GitHub issues GitHub license

glTFast enables loading glTF™ (GL Transmission Format) asset files in Unity.

It focuses on speed, memory efficiency and a small build footprint.

Two workflows are supported

  • Load glTF assets at runtime
  • Import glTF assets as prefabs into the asset database at design-time in the Unity Editor

Try the WebGL Demo and check out the demo project.


glTFast supports the full glTF 2.0 specification and many extensions. It works with Universal, High Definition and the Built-In Render Pipelines on all platforms.

See all details at the list of features/extensions.


The easiest way to install is to download and open the Installer Package

It runs a script that installs glTFast via a scoped registry.

Afterwards glTFast and further, optional packages are listed in the Package Manager (under My Registries) and can be installed and updated from there.

Optional dependencies

Alternative: Install via GIT URL

Add glTFast via Unity's Package Manager ( Window -> Package Manager ). Click the ➕ on the top left and choose Add package from GIT URL.

![Package Manager -> + -> Add Package from git URL][upm_install]

Enter the following URL:

To add support for Draco mesh compression, repeat the last step and also add the DracoUnity packages using this URL:

> Note: You have to have a GIT LFS client (large file support) installed on your system. Otherwise you will get an error that the native library file (dll on Windows) is corrupt!

glTFast 2.x requires Unity 2019.3 or newer. For older Unity versions see Legacy Installation.


You can load a glTF asset from an URL or a file path.

Runtime Loading via Component

Add a

component to a GameObject.

GltfAsset component

Runtime Loading via Script

var gltf = gameObject.AddComponent();
gltf.url = "";

See Runtime Loading via Script in the detailed documentation for instructions how to customize the loading behaviour via script.

Customizing Runtime Loading Behavior

The loading behavior can be highly customized:

  • Customize instantiation
  • Load glTF once and instantiate it many times (see example)
  • Access data of glTF scene (for example get material; see example)
  • Load reports allow reacting and communicating incidents during loading and instantiation
  • Tweak and optimize loading performance

See the Documentation for details.

Editor Import

To convert your glTF asset into a native Unity prefab, just move/copy it and all its companioning buffer and texture files into the Assets folder of your Unity project. It'll get imported into the Asset Database automatically. Select it in the Project view to see detailed settings and import reports in the Inspector. Expand it in the Project View to see the components (Scenes, Meshes, Materials, AnimationClips and Textures) that were imported.

Project Setup

Materials and Shader Variants


glTFast uses custom shaders that you have to include in builds in order to make materials work. If materials are fine in the Unity Editor but not in builds, chances are some shaders (or variants) are missing.

Read the section Materials and Shader Variants in the Documentation for details.


Find plans for upcoming changes at the milestones.



  • Stay fast, memory efficient and small
  • Feature completeness
    • Support 100% of the glTF 2.0 specification
    • Support all official Khronos extensions
    • Support selected vendor extension
  • Universally usable…
    • …across all popular Unity versions
    • …across all platforms and devices
    • …across different project setups (all important render pipelines, GameObject or entity component system based, DOTS, Tiny, etc.)
  • Allow customization

Extended goals

  • glTF Authoring (create optimized glTFs from prefabs)
  • glTF Runtime Export

Get involved

Contributions like ideas, comments, critique, bug reports, pull requests are highly appreciated. Feel free to get in contact if you consider using or improving glTFast.


Unity Technologies

Thanks to Embibe for sponsoring the development of skin support! ❤️


Copyright (c) 2020-2021 Andreas Atteneder, All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use files in this repository except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.


Unity is a registered trademark of Unity Technologies.

Khronos® is a registered trademark and glTF™ is a trademark of The Khronos Group Inc.

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.