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GLB to 3MF converter

Convert a GLB or glTF scene into a 3MF package on your own machine. This is the best route from a web or game asset to a print file, because 3MF is the one target here that can hold both a real unit and the material colours the glTF already carries.

Drop your GLB files here

STL, OBJ, PLY, GLB, glTF, 3MF, SVG and DXF. Nothing is uploaded: files are read and converted inside this tab. Checking what this device can handle...

Queue

No files yet. Drop models above, or use the file picker.

Add a model to see it here.

Output

Convert toDXF and SVG need a 2D source. A mesh cannot become a drawing without choosing a projection, which is yours to decide, not ours to guess.Encoding

3MF has one encoding.

Units

Assign unitLabel the existing numbers. Nothing is rescaled.Convert unitRescales so the physical size stays the same.

Size and placement

ScalingOrientation

Rotate X°Rotate Y°Rotate Z°

Centre on bedCentres X and Y, and sits the model on Z=0.

Repair and cleanup

These can change the shape, so they need a before-and-after review before export.

Safe repairWelds duplicates, drops zero-area triangles and fixes winding. Never fills holes.Weld duplicate verticesRemove zero-area trianglesWeld tolerance

Vertices closer than this are merged.Merge all meshes into oneNormals

Inspection

Add a model to see its dimensions, mesh health and estimated volume.

What this GLB to 3MF conversion does and does not do

glTF is defined in metres and 3MF declares whatever unit you choose, so the geometry is scaled on export. A 0.2 m model exported as millimetres becomes 200 mm, which is almost always what you want.
Base colour and opacity become 3MF base materials. Texture images are never extracted from the GLB or embedded in the 3MF, so a textured asset arrives as flat per-material colour.
The glTF scene graph is flattened: node transforms are baked into vertices and each mesh becomes a 3MF object instantiated once in the build section, with no hierarchy retained.
Animations, skins, morph targets, cameras and lights are ignored, because a 3MF describes a static thing to manufacture.
Draco and meshopt compressed geometry is refused with a clear message rather than partly read. Re-export without mesh compression.
Web and game assets are frequently not solid. The inspection panel counts open edges, non-manifold edges and shells so you find out before your slicer does.

Troubleshooting

The model is 200 times too small

Check the unit conversion. glTF measures in metres; if the 3MF was written declaring metres too, a 0.2 m model is 0.2 of a unit. Export declaring millimetres instead.

My slicer says the mesh is not watertight

Game and web assets often are not: they only ever needed to look right from outside. Open the inspection panel for the open-edge and shell counts. Safe repair fixes duplicates, degenerate triangles and winding, but never fills holes.

The textures are gone

Texture images are never read or written here. Material colours are carried; a textured model becomes flat coloured objects, and the workspace lists what the source referenced.

It is refused because it needs Draco

Draco is a compression extension needing its own decoder. Re-export from your tool with mesh compression off and the file will open.

Questions

Why 3MF rather than STL for a GLB?

Because STL would throw away both the unit and the colour, and a GLB has both. 3MF keeps them, so the print file still describes what you designed.

Will the colours print?

That depends entirely on your printer and slicer. The 3MF records base materials correctly; whether the hardware can reproduce them is outside this converter.

Is the export verified?

Yes. Every 3MF is re-opened and its triangle count, mesh count, bounding box and declared unit are checked against what the writer was asked to produce.