Reading a GLB like a production file

File size is a symptom. The causes are almost always uncompressed images, 8K uniquely-mapped sets, and a material per object.

What we parse

The analyzer reads the GLB container (JSON + BIN) in your browser. Image dimensions come from PNG/JPEG/WebP/KTX2 headers — the pixels are not decoded. Triangle counts come from accessor counts, so Draco meshes still report geometry without a full decode.

External .gltf + .bin + images are only complete if you pack them to .glb first.

Health flags

Web and Unreal use different thresholds. A 120 MB photogrammetry mesh can be a reasonable Unreal import and an impossible WebGPU download. Switch the profile on the tool.

Draw calls

Primitive count is a lower bound on draw calls if each primitive is a separate pass. Instancing, Nanite, and batching change the runtime number — the analyzer reports the asset, not the renderer.

Tools for this task

GLB / GLTF Analyzer — Triangles, textures, materials, and compression for a GLB or glTF.