Free glTF (.gltf) to STL (.stl) converter — running entirely in your browser. No upload, no signup, no file limits: your files never leave your device.
STEP · IGES · BREP · STL · OBJ · PLY · GLB · glTF · 3MF · COLLADA · AMF · FBX · 3DS · OFF · LAS · PCD · XYZ · PTS
glTF is the Khronos royalty-free standard for transmitting 3D scenes. The JSON variant keeps the scene description human-readable with geometry in sidecar buffers, and the ecosystem — Babylon.js, Unity, Unreal, Blender and the browser engines — treats it as the native interchange format for real-time 3D.
STL is the de-facto standard for 3D printing. It describes a model purely as a mesh of triangles — no color, no units, no assembly structure — which makes it simple, universally supported, and the required input for virtually every slicer, from PrusaSlicer and Cura to resin-printer tools.
| glTF | STL | |
|---|---|---|
| Geometry | GPU-ready triangle mesh | Triangle mesh |
| Units | Meters by spec | No — unitless numbers |
| Colors & materials | Full PBR materials | No |
| Animations | Yes | No |
| Typical use | Real-time engines & web pipelines | 3D printing |
Yes — free with no accounts, no watermarks and no file-size limits. Conversion runs on your own machine, so there are no server costs behind it.
No. The converter runs entirely in your browser using WebAssembly. Your .gltf file never leaves your device, which makes it safe for confidential designs.
Yes — parts and assembly hierarchy are preserved where STL supports them, and you can optionally merge everything into a single mesh during conversion.
Yes. Every converted model opens in the built-in 3D viewer with an assembly tree, display modes and section views, so you can inspect the result first.
glTF can contain textures and animation, but this converter carries geometry, hierarchy and one flat base color per part; texture maps, rigs and animation tracks are omitted. The STL result also has no units, colors, material data or part names, so keep the source alongside it.
Which file format should you actually print from? A practical ranking of STL, OBJ, 3MF and AMF for FDM and resin printing, with free conversion tools.
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