GLB and a 3D city map: download a buildings model in GLB, OBJ or STL

You're searching for "download a 3D map in GLB", or someone sent you a .glb file and it's unclear how to open it. Let's keep it simple: what GLB is, how to open it on desktop and online, and how to download a 3D city buildings model straight in the format you need — with real heights.

What GLB is

GLB is the binary version of the glTF format (GL Transmission Format). glTF is called "the JPEG of 3D": a compact, fast-loading format for 3D scenes and models. Plain glTF splits into several files (.gltf + geometry + textures), while GLB packs everything into one binary file — easy to move and open. Inside are building geometry, materials and, if needed, textures.

How to open GLB

Windows. On recent Windows versions GLB opens in the built-in "3D Viewer" app — double-click and the model spins in a window. If the app isn't there, it installs free from the Microsoft Store.

Online viewers. The easiest is to drag the .glb into a web viewer. Sketchfab, the Babylon.js Sandbox and other online viewers show the model with nothing to install. Many engines (three.js, Cesium) also load GLB natively — it's the web standard.

Blender. For editing — Blender opens GLB via File → Import → glTF 2.0 (.glb/.gltf). From there you can change geometry, materials, and export to other 3D formats.

A technical breakdown is in the GLB deep dive and the glTF deep dive.

How to download a 3D city buildings model

If you need not an abstract model but a real city in 3D — select an area and download the buildings straight to GLB. OpenStreetMap building footprints are extruded using floor count/height from the tags, and you get a ready 3D scene of a block or city center in a single file.

Need a different 3D format for your task:

• OBJ — universal exchange, read by almost any 3D editor;
• STL — for 3D-printing a city model.

How building extrusion works and which height tags are used is covered in Exporting 3D buildings and the 3D map export guide.

In short

• GLB is a binary glTF, the whole 3D model in one file; it opens in the Windows "3D Viewer", online viewers and Blender.
• Need a 3D city model — download the buildings in GLB, OBJ or STL.