⚠ Immersive Scaler is being removed in Cats 5.2.5.0. The external Immersive Scaler is no longer maintained by its author, so we are replacing it with our own scaler built directly into Cats. Until then, the current integration still works as described below.

Overview

Proper avatar scaling is crucial for VR experiences:

Ensures comfortable viewing in VR
Maintains correct proportions relative to the world
Meets platform height recommendations
Provides better social interaction in VR

Requirements

The Scaling panel requires the Immersive Scaler plugin to be installed.

Immersive Scaler Requirements

For Blender 5.1+: Download from Immersive Scaler Repository - Version 1.0.0.0 or higher
For Blender 4.x or older: Use the original Immersive Scaler - Version 0.5.2 or higher

Installation States

The Scaling panel adapts based on Immersive Scaler status:

When Immersive Scaler is NOT Installed

The panel shows:

Installation instructions
Direct download link
Explanation of features

To install:

Download from the link provided
Install via Edit > Preferences > Extensions
Restart Blender
Return to Scaling panel

When Immersive Scaler is Disabled

The panel shows:

Quick enable button
No restart required
Click to activate instantly

To enable:

Click the Enable button
Immersive Scaler activates immediately
Scaling features become available

When Immersive Scaler is Active

Full scaling features are available:

Height measurement tools
Scale reference objects
Platform-specific guidelines
Conversion utilities

Key Features

Once Immersive Scaler is installed and active, you'll have access to:

Model Scaling Tools

Accurate Height Measurement:

Measure avatar height in real-world units
Measure in meters, feet, inches
Account for foot position and head top
Get accurate measurements

Real-World Size References:

Compare to real human heights
See how avatar will appear in VR
Understand scale relative to environments

Scale Operations:

Scale to specific height
Scale by percentage
Maintain proportions
Preserve armature and mesh together

Measurement Tools

Height Markers:

Visual height reference in viewport
Shows common height marks
Helps visualize final size
Removable reference objects

Scale Reference Objects:

Doors, chairs, tables
Common objects for size comparison
Helps understand avatar scale
Can be deleted after measurement

Unit Conversion:

Convert between metric and imperial
Meters, centimeters, feet, inches
Easy understanding of measurements

Custom Measurement Points:

Measure from specific bones
Account for custom rigs
Handle non-standard models

Platform Support

VRChat Height Guidelines:

Recommended: 160cm - 180cm (5'3" - 5'11")
Optimal: 165cm (5'5") for average view
Too tall: Over 200cm (6'7") - may cause issues
Too short: Under 140cm (4'7") - may cause issues

ChilloutVR Size Standards:

Similar to VRChat recommendations
160cm - 180cm comfortable range

Resonite Scaling References:

Flexible scaling options
Supports wider range

Universal VR Measurements:

Works across platforms
Standard height references
Comfortable viewing ranges

Using Immersive Scaler

For detailed information about using Immersive Scaler features:

Install and enable Immersive Scaler
Visit the Immersive Scaler Repository for documentation
Check the repository's wiki for tutorials
Explore the tool's interface in Blender

Basic Workflow

Import your model using Quick Access
Open Scaling panel
Ensure Immersive Scaler is active
Measure current height
Scale to desired height
Verify with reference objects
Export model

Best Practices

Recommended Avatar Heights

For VRChat:

Height Range	Description	Use Case
165cm (5'5")	Ideal average	Most versatile, comfortable for all
160-170cm	Comfortable range	Good for most avatars
150-160cm	Shorter avatars	Cute characters, children
170-180cm	Taller avatars	Tall characters, warriors
140-150cm	Very short	Chibi, small creatures
180-200cm	Very tall	Giants, monsters (use sparingly)

General Guidelines:

Too short: Hard to interact with world objects
Too tall: Can clip through ceilings, appears intimidating
Average: Most comfortable for social interaction
Consider your avatar type and use case

When to Scale

Scale BEFORE:

Setting up eye tracking
Setting up visemes
Creating shape keys
Final optimization
Exporting

Scale AFTER:

Importing model
Fixing MMD model
Basic mesh cleanup

Testing Scale

In Blender:

Add reference objects
Compare to human-scale references
Check proportions

In VRChat:

Test in-game before finalizing
Ask others how you appear
Check mirror view
Test interaction with world objects

Common Scale Issues

Avatar Appears Wrong Size in VRChat

Possible causes:

Scaled incorrectly in Blender
Export settings wrong
Unity import scale issues

Solutions:

Verify height in Blender with Immersive Scaler
Use correct export settings in Cats
Check Unity import scale (should be 1.0 for FBX)

Scaling Breaks Shape Keys

This shouldn't happen with proper tools, but:

Scale before creating shape keys
Use proper scaling tools (not just manually resizing)
Immersive Scaler handles this correctly

Proportions Look Wrong After Scaling

Possible causes:

Non-uniform scaling
Only scaled mesh, not armature
Only scaled armature, not mesh

Solutions:

Use Immersive Scaler's scale tools (scales both together)
Apply transforms after scaling
Check both armature and mesh were scaled

Integration Notes

With Optimization

Scale before or after optimization:

Doesn't significantly affect Optimization tools
Bone merging works at any scale
Atlas creation works at any scale

With Export

Using Quick Access export:

Cats handles scale correctly
FBX export maintains scale
No additional settings needed

Related Pages:

Quick Access - Import/Export
Merge & Attach - Merging models
Troubleshooting - Scale issues

External Resources:

Immersive Scaler Repository - Detailed documentation
VRChat Avatar Scaling Guidelines

Please do not report any issues for Blender versions below 5.1 (supported: 5.1 and 5.2, recommended 5.2 LTS)

📖 This wiki documents Cats 5.2.3.0 (upcoming). For 5.2.2.0 and earlier, see the legacy wiki.