In the right-hand properties sidebar, look for the newly added tab.
Best if you are already preparing an avatar for platforms like VRChat.
pip install gltf-vrm-export
For a full, production-ready VRM avatar, using the Blender VRM Add-on is recommended to ensure that blend shapes, materials, and physics are properly configured for VTubing software. convert glb to vrm full
This report outlines a complete workflow to convert GLB (GLTF Binary) files to VRM (VRM 0.x — Unity-based humanoid avatar) including prerequisites, tools, step-by-step procedures (automated and manual), common issues and fixes, validation, optimization, and recommended pipeline for production use.
Disclaimer: Make sure you have the rights to the 3D model you are converting, especially if it is being used in public VR environments.
| Problem | Cause | Solution | | :--- | :--- | :--- | | | Rotation/Scale not applied | Apply transforms ( Ctrl + A > All Transforms ) before export. | | Blink/Smile not working | No shape keys or wrong naming | Use CATS to auto-generate Blend Shapes from vertex groups. | | Arms twist unnaturally | Twisted bone roll in GLB origin | In Blender, select armature, go to Edit Mode , select bone > Clear Roll or Recalculate Roll . | | Eyes are not tracking | Eyes are not separate meshes | In VRM export settings, manually designate the left/right eye meshes. | In the right-hand properties sidebar, look for the
A standard Unity installation doesn't speak VRM. Leo needed a translator. He opened the Package Manager and imported the .
import json import numpy as np from pathlib import Path
If hair stretches infinitely, a bone might be missing a parent-child relationship in the original skeleton. This report outlines a complete workflow to convert
| Problem | Likely Cause | Solution | | :--- | :--- | :--- | | | GLB is a static prop (like a tree or a rock), not a character. | Find a properly rigged GLB. You cannot convert a rock into an avatar. | | Eyes don't blink / Mouth doesn't move | GLB lacks blendshapes/morph targets. | You must manually create blendshapes in Blender before conversion. | | Model looks twisted or broken in VRM | Incorrect bone orientation or weight painting. | In Unity, re-configure the Humanoid rig. In Blender, check that all bones face the correct direction (Y-axis up, X-axis right). | | File size is huge (over 50 MB) | GLB has high-resolution textures and many vertices. | Use Unity to compress textures or reduce mesh quality. VRM has file size limits for some platforms. |
| Problem | Fix | |--------|-----| | No humanoid bones | Use Mixamo auto-rig, then export as FBX → GLB | | VRM export missing face expressions | Add blend shapes in Blender/Unity | | Texture missing | Re-link images in Blender’s Shader Editor | | Rotation wrong | Apply rotation/scale before export |
Remove unnecessary objects, meshes, or empty nodes that might cause issues during export. 3. Setting Up VRM Components