Free STL to GLB converter
Convert STL to GLB for web viewers.
Put a 3D-printable model on a web page or in AR. Drop an STL and download a compact GLB that model-viewer, three.js, Babylon.js and Blender open directly.
Why convert STL to GLB?
GLB files are much smaller than STL because vertices are shared and the format is built for streaming, so they load faster on product pages and in web viewers.
How to convert STL to GLB
- Choose your STL file above, or drag it onto the box.
- Check that GLB is selected. You can switch to any other output.
- Select Convert. The file downloads straight away. Nothing is uploaded.
Good to know
- STL has no units, so the GLB keeps the STL's numbers as metres. Scale by 0.001 if your STL is in millimetres and real-world size matters (for example in AR).
- The model is rotated from CAD's Z-up to glTF's Y-up.
What converts, and what doesn't
- Every output is a triangle mesh. STEP and IFC solids are tessellated for display, so the result is not an editable solid or B-rep.
- When the source names its parts (STEP and IFC assemblies, for example), they become named groups in OBJ. STL, PLY and GLB hold a single combined mesh.
- Colours and materials are not carried over.
- Coordinates keep the source units, except GLB, which is scaled to metres when the source declares its units.
Frequently asked questions
Why is my model huge in AR?
STL stores no units, so a part modelled in millimetres comes through as metres. Scale it by 0.001 in your viewer or in Blender.
Is my file uploaded?
No. The file is read and converted by the Caddis engine running inside your browser tab. It is never sent to a server, so confidential drawings stay on your device.
Is it really free?
Yes. There's no account, watermark, page limit or daily quota. The converter runs on your own computer, so it costs us nothing per file.
Need to measure or mark up the drawing too?
The same engine powers the free Caddis viewer on the web and on iPhone. Open DWG, DXF, STEP and STL files, measure, and add markup, all on your device.
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Universal CAD converterDWG version checkerDWG to DXFDWG to PDFDWG to SVGDWG to PNGDXF to PDFDXF to SVGDXF to PNGDXF to R12 DXFSTEP to STLSTEP to OBJSTEP to GLBSTL to OBJOBJ to STLPLY to STLIFC to OBJIFC to GLBSLDPRT to STL