The GLB file format is the binary container version of glTF (GL Transmission Format), a royalty-free specification developed by the Khronos Group and widely adopted for real-time 3D on the web. A single .glb file packs together geometry, materials, textures, animations, and scene hierarchy into one compact binary blob — making it the de-facto format for WebGL, AR/VR, game engines, and platforms like Sketchfab or Google Model Viewer.
While GLB excels at web delivery, the 3D-printing world revolves around STL (Standard Tessellation Language) — a format introduced by 3D Systems in 1987 that represents surfaces as a mesh of triangles. Nearly every slicer on the market, from Cura to PrusaSlicer to Bambu Studio, accepts STL as its native input. When you want to take a model you received or built in a web-centric pipeline and send it to a printer, converting GLB to STL is the essential first step.
A common question is: how do I convert a GLB file to STL? The straightforward answer is to use an online GLB converter like the one on this page. The tool reads the binary glTF buffer, extracts every mesh primitive's vertex positions and face indices, transforms them by the node's world-space matrix (so scale, rotation, and translation are baked in), and writes each triangle as an STL facet record. For Binary STL the result is a compact 80-byte header followed by a 4-byte triangle count and 50 bytes per triangle. For ASCII STL each facet becomes a human-readable block of text — useful for debugging but roughly 5× larger.
One gotcha to be aware of when going from glb to stl: unit scale. glTF specifies that 1 unit equals 1 metre. Many CAD tools and slicers assume 1 unit equals 1 millimetre. If your converted model looks 1000× too large or small in your slicer, use the ×1000 scale toggle before converting — this multiplies every vertex coordinate so the mesh arrives at the correct size without any manual resizing in the slicer.
Textures and material colours are not preserved in STL, because the format only stores geometry. If you need colour information for multi-material printing, consider exporting to OBJ+MTL or 3MF instead. But for the vast majority of single-material FDM and resin prints, a clean STL from a GLB source is everything you need to go from digital model to physical object.