glTF vs GLB vs OBJ: Choosing a 3D Format for the Web

If you are putting 3D on a website — a product viewer, a configurator, a WebXR scene — the format you ship decides your loading time and your material quality. Here is how the three most common candidates compare.

OBJ: universal but ancient

OBJ is plain text from the 1990s. Every tool exports it, which is why it survives, but it has no PBR materials (only the dated MTL sidecar), no animation, no compression, and text parsing is slow. Use it as an interchange format between tools — not as the format you serve to browsers.

glTF: the standard for real-time 3D

glTF 2.0 was designed for exactly this job: geometry stored GPU-ready, a full PBR material model, animations, and first-class support in three.js, Babylon.js, <model-viewer>, Unity and Unreal. The .gltf variant is a JSON file with separate buffers — readable, but multiple requests.

GLB: glTF in one file

GLB packs the same glTF scene into a single binary file: one request, smaller size, no path headaches. For delivery, GLB is almost always what you want; keep .gltf for debugging and hand-editing. With Draco compression (which our viewer reads natively), geometry shrinks several-fold again.

Practical recommendation

• Shipping to users: GLB — one file, compact, instant GPU upload.
• Passing between artists and tools: OBJ or glTF, whichever the toolchain prefers.
• Coming from CAD? Convert STEP to GLB directly — tessellation and packaging in one step, right in the browser.

You can convert any supported mesh with the free tools here: OBJ to GLB, FBX to GLB, STL to glTF — no uploads, no accounts.