Convert STL to GLB - Free Online Converter
Drop a .stl file below and download it as .glb in seconds. The conversion runs entirely in your browser - no upload, no signup, no watermark. The output loads in every web viewer, engine, and AR pipeline.
Updated July 2026
Done in seconds
Your STL converts to GLB locally in your browser - no upload queue, no waiting.
Private by design
Your file never leaves your device. Nothing is uploaded, nothing is stored.
Free, no strings
No signup, no watermark, no file limit - convert as many files as you need.
How to convert stl to glb
Drop your STL file
Drag the .stl file into the converter above or click to browse. No account and no upload - the file stays on your device.
Conversion runs in your browser
The model is parsed and rewritten locally, in seconds for typical files. Geometry is carried over 1:1 - no remeshing, no quality loss.
Download the GLB
The .glb download starts from the same spot. Convert as many files as you like - there is no limit or watermark.
STL and GLB, explained
What is STL?
STL is the oldest and most universal 3D printing format. It describes a model as a plain list of triangles - nothing else. No colors, no materials, no units, no object names. That simplicity is exactly why every slicer, CAD tool, and print service on earth accepts it.
An STL file stores each triangle as three corner points plus a facet normal, either as compact binary (the common case) or human-readable ASCII. Because the format carries no unit information, almost every tool assumes millimeters. When a file needs to work absolutely anywhere, STL is still the safe answer.
- Developed by
- 3D Systems (1987)
- Structure
- Binary or ASCII list of raw triangles
- Used by
- Every slicer, CAD package, mesh-repair tool, and 3D-printing marketplace
What is GLB?
GLB is the binary form of glTF, often called "the JPEG of 3D". One file packs the full scene: meshes, PBR materials, embedded textures, animations, and a real unit scale (meters). It is the standard for 3D on the web and the default output of most AI 3D generators.
Because everything is embedded in a single binary file, GLB transfers cleanly between tools with nothing lost in transit. glTF/GLB is an open Khronos standard, loads fast, and is supported by every modern engine, DCC tool, and web viewer.
- Developed by
- Khronos Group (2015)
- Structure
- Single binary file: JSON scene + buffers + textures
- Used by
- Web viewers, Three.js, Unity, Unreal, AR apps, e-commerce platforms
What survives the stl to glb conversion
Format conversion is honest work: some data has nowhere to go in the target format. Here is exactly what carries over.
Triangle geometry
Every triangle is carried over exactly - no remeshing or decimation.
Smooth shading
STL stores flat facets; vertex normals are computed during conversion so the GLB shades smoothly where the geometry allows.
Model scale
Numbers copy 1:1. STL is read as millimeters, GLB as meters - a print-scale model may import 'large' in strict glTF tools; scale by 0.001 there if needed.
UV coordinates
STL has no UVs; the GLB arrives without them. UV-unwrap before texturing.
Colors & materials
STL stores no appearance data - the GLB gets a neutral material, ready to be textured.
When should you convert STL to GLB?
Convert to GLB to show a print file on a screen: embedding a model on a website, sharing an interactive preview, importing into an engine, or preparing for AR - none of which read STL.
Keep the STL for the printer - slicers neither need nor want GLB. This conversion is for the display/digital branch of the workflow.
Still weighing the formats themselves? See the full GLB vs STL comparison - structure, materials, file size, and which wins for each use case.
And if what you actually need is a new model rather than a new file format: 3D AI Studio's main tool can generate 3D models from photos with AI - with exports to every format on this page.
STL to GLB - frequently asked questions
Made with 3D AI Studio
Need new game assets, not just a format swap?
3D AI Studio creates game-ready 3D assets from images or text with AI - textured, exportable to GLB and FBX, and usable in Unity or Unreal. 100 free credits per month.