How to optimise 3D models for the web, augmented reality and virtual reality
optimising a 3D model means reducing it to what is essential so that it loads quickly and runs smoothly on a mobile, without losing the quality that matters: simplifying the geometry, compressing and sizing the textures, reducing the number of materials, using suitable formats (GLB for web and Android, USDZ for iOS) and testing on real devices.
Why optimisation is critical
An engineering or rendering model can weigh hundreds of megabytes and have millions of polygons. On a website or a mobile that means:
- Slow loading and abandonment.
- Juddering images.
- Failures on mid-range devices.
- Higher consumption of data and battery.
In VR, smoothness is even more critical: a low frame rate causes discomfort and motion sickness.
What is optimised
1. Geometry (polygons)
- Remove what is not seen (interiors, hidden screws).
- Reduce the mesh in flat or less relevant areas.
- Keep greater detail in silhouettes and key parts.
- Use normals and maps to simulate detail without adding polygons.
2. Textures
- Size them according to use: a 4K texture is not needed on a small object on mobile.
- Compress with efficient formats.
- Group several textures into atlases where possible.
- Take care of colour consistency between screens.
3. Materials
- Reduce the number of materials (each one is an additional load for the device).
- Use standard physically based materials (PBR) so they look right on different platforms.
- Avoid costly effects (multiple transparencies, complex reflections) unless they add something.
4. Structure and hierarchy
- Clear names for parts.
- Correct origin and scale (in metres).
- Consistent orientation.
- Separate parts only when they are needed (configurators, animations).
5. Animations
- Few and well defined.
- Avoid animations with many bones or heavy exports.
Common formats
| Format | Main use | Notes |
|---|---|---|
| GLB / glTF | Web, Android, many AR platforms | Open standard, lightweight |
| USDZ | AR on iPhone and iPad (Quick Look) | Apple-specific |
| FBX / OBJ | Exchange between programs | Not ideal for the web |
| STEP / CAD | Engineering | Requires conversion |
GLB + USDZ is usually delivered to cover the web and the two major mobile ecosystems.
Starting references (indicative)
Optimum limits change according to the device and the platform, but as general guidance:
- Web and AR on mobile: models of at most tens of thousands of polygons and a total weight of a few megabytes.
- Standalone VR: a tighter polygon and material budget than on PC.
- Highly detailed products: the content is split into levels of detail or loaded in parts.
Confirm the numbers with your platform and run tests.
Recommended process
- Define the destination (web, AR, VR) and the minimum device.
- Start from the master model of high quality.
- Create an optimised version for each destination.
- Check visually that what matters is preserved.
- Measure weight and performance.
- Test on real mobiles, including a mid-range one.
- Adjust and document the parameters for future models.
Common mistakes
- Using the engineering model as it is.
- Huge textures on small objects.
- Too many materials.
- Incorrect scale in AR.
- Not testing on iPhone and Android.
- Excessive compression that destroys colour quality.
Key ideas
- Optimisation decides whether the experience works or not.
- Reduce polygons, textures and materials to what is needed.
- Deliver GLB and USDZ to cover the main environments.
- Keep a master model and derive versions from it.
- Always test on real devices.
Frequently asked questions
Is quality lost when optimising?
What is not perceived is reduced. Done well, the model looks practically the same on screen.
How much should a model for AR weigh?
The less, the better; a few megabytes is a common reference, but confirm it with your platform.
Can it be automated?
Partly, with decimation and compression tools; human judgement is still needed.
Do models have to be optimised for each channel?
Ideally, yes: web/AR and VR have different requirements.
More guides on this topic
How interactive 3D can help explain complex products
How interactive 3D helps explain complex products: cutaway views, exploded views, animations, hotspots and layers of information for sales, support and training.
How to turn a physical product into an interactive 3D model
Methods for digitising a physical product in 3D: modelling from CAD and references, 3D scanning and photogrammetry. Process, requirements and how to make it interactive.
How to reuse the same 3D asset in marketing, sales and training
How to make a 3D model pay: images, video, web, AR, VR, configurator, trade fairs, training and support. Single-asset strategy and version management.