Web 3D lives under constraints that offline rendering never faces. A model built for a campaign film can have millions of polygons and gigabytes of textures. On a product page, it has to appear within a few seconds on a phone over mobile data.
Optimising for that is part of the design work.
Choose the right format#
glTF, and its binary form GLB, has become the common format for 3D on the web. It is compact, widely supported, and designed to be loaded directly by browsers and viewers.
Reduce what the viewer never sees#
Most product models carry detail that disappears at screen size. Interior parts, hidden faces and tiny bevels all add weight.
Practical reductions#
- Remove geometry that is never visible
- Decimate meshes to the lowest polygon count that still holds the silhouette
- Bake fine detail into normal maps instead of geometry
- Reuse materials and textures across parts
Compress the textures#
Textures are often the heaviest part of a model. Reduce their resolution to what the viewer actually displays, and use compressed formats such as KTX2 where your viewer supports them. Geometry can be compressed too, for example with Draco.
Load only on request#
Show a lightweight poster image first, and load the 3D viewer when someone chooses to interact. Everyone gets a fast page, and the people who want to explore pay the cost of the download.
A model that loads fast and looks good beats a perfect model nobody waits for.
Light it like a photograph#
Good lighting does more for perceived quality than extra polygons. A simple environment map and soft shadows make an optimised model look considered rather than cheap.
Measure on a real phone#
Check the total download size of each model and time how long it takes to appear on a mid-range phone over mobile data. Set a budget, for example a few megabytes per model, and treat it like any other performance target.
