Convert GLB to 3MF
Convert GLB to 3MF in your browser. The conversion runs on this page and the file never leaves your computer.
Result
Before you convert: what this keeps and what it destroys
Preserved
- The geometry, triangle for triangle
- Overall dimensions and proportions
- Watertightness, where the input is watertight
- The unit, recorded in the file
- Colour
- Separate parts and their positions
Destroyed
- Animation, rigs, cameras and lights, if the file has them
↺ the reverse: 3MF → GLB · about .glb · about .3mf · just view it instead
Why people convert GLB to 3MF
Printing something you found rather than modelled: a Sketchfab download, a photogrammetry scan, an asset from a product pipeline.
3MF is the right target for that and better than STL in every respect that matters here. It records the unit, so the size stops being a guess. It keeps colour, which a downloaded model usually has and STL would throw away. And it keeps the GLB's separate nodes as separate objects on the build plate.
The scale conversion is the thing to check. glTF is metres and 3MF is written here in millimetres, so every coordinate is multiplied by 1000. A model authored at 0.05 in glTF units becomes 50 mm, which is almost certainly what the author intended. If the result comes out absurd, the source was not really in metres, which is common in files exported from game engines.
What you get
You get a binary 3MF file containing the same triangles the GLB file described. No geometry is added, removed or approximated: mesh-to-mesh conversion is a change of container, and this site's tests check that the triangle count comes out identical.
Carried across: the unit, recorded in the file, supported base or vertex colour, the supported part structure.
The conversion runs in your browser. Your file stays on your computer and is not uploaded.
What to check afterwards
- glTF and GLB use metres by specification. This converter interprets the source coordinates that way. If the model was authored at a different scale, confirm a known dimension before using the output.
- The numbers change. 3MF is read in millimetres and GLB in metres, so every coordinate is rescaled. The result is the same physical size, but the numbers in the file are different numbers.
If you need something this conversion cannot give you
This pair loses very little. 3MF carries what GLB carries, so the main reason to choose a different target is what the receiving software accepts.
Going the other way
Convert 3MF back to GLB. The reverse conversion also works with mesh geometry. It does not reconstruct exact CAD surfaces. Material data and part structure lost in either direction cannot be restored by converting back. Keep the original file for later edits.
How we know this conversion works
This pair was checked against 7 files from the test corpus on 2026-09-04. Each run parses its own output back in and compares the bounding box, the triangle count and, for closed solids, the volume against the input.
A pair that fails those checks doesn't get a page. That's why this site lists 120 conversions and not the several hundred a format-times-format grid would suggest.