Free 3D converter

Convert GLB to 3MF

Drop a GLB file and download it as 3MF, scaled and set on the build plate. The conversion runs in your browser, so the file never leaves your device. It keeps the exact shape and a real size in millimetres.

Free, no sign-up, and your file stays on your device.

Drop a GLB file here

Converted to 3MF in your browser. Nothing is uploaded.

GLB, glTF, OBJ, STL, PLY, FBX or 3MF, up to 300 MB. Add .mtl, .bin and texture files alongside.

What carries over from GLB to 3MF

Checked against what the converter writes, not just what the formats allow.

Shape (triangles): Kept exactly
UV coordinates: Dropped: 3MF can't store it
Colour texture: Dropped: 3MF can't store it
PBR maps (roughness, metalness, normal): Dropped: 3MF can't store it
Vertex colours: Dropped: 3MF can't store it
Animation: Dropped: 3MF can't store it
Separate parts: Kept as separate objects
Size and units: Metres become millimetres, or the model is scaled to the height you set (100 mm by default).
Up direction: Turned Z up and set flat on the build plate.

How to convert GLB to 3MF

Add your GLB
Drop the .glb file or choose it from your device.
Check the preview
Turn the model, check its triangle count, and set the height you want to print in millimetres.
Download the 3MF
The .3mf is written in a second or two for most models.

When to convert GLB to 3MF

To print at the right size
3MF records millimetres, so the model can't arrive 1,000 times too big or too small the way an STL sometimes does.
To start a slicer project
Bambu Studio and PrusaSlicer save their projects as 3MF, so the file drops straight into the same workflow.

The two formats

GLB

Binary glTF 2.0

GLB is the single-file, binary form of glTF 2.0, the open format the Khronos Group published in 2017 for delivering 3D assets. Mesh, materials, textures and animation all travel in one file.

Usually comes from: AI 3D generators (including PhotoGenius), Sketchfab downloads, web 3D projects and game asset stores
Opens in: Blender, Godot, three.js and most web viewers, Android's Scene Viewer, Bambu Studio and UltiMaker Cura, Unreal's glTF importer, and Unity with the glTFast package
Units: Metres
Up axis: Y up

3MF

3D Manufacturing Format

3MF is an open, zip-based XML format from the 3MF Consortium (founded in 2015) built to replace STL for printing. Unlike STL it records units, so a model always opens at the right size.

Usually comes from: Bambu Studio and PrusaSlicer projects, MakerWorld and Printables downloads
Opens in: every major slicer: Bambu Studio, PrusaSlicer, OrcaSlicer, UltiMaker Cura and Lychee
Units: Recorded in the file (millimetres when written here)
Up axis: Z up

Need a model to convert?

Make one with AI from a photo or a sentence, then download it as GLB and convert it here.

Questions

Something else? Ask us and a person will answer.

Is this GLB to 3MF converter free?

Yes. There is no account, watermark or limit on conversions. It accepts files up to 300 MB; how large a model your browser can handle depends on your device's memory.

Is my file uploaded?

No. The conversion runs in your browser with the open-source three.js loaders and exporters, so your GLB never leaves your device.

Why is my 3MF the wrong size in the slicer?

GLB is measured in metres and slicers read 3MF in its stated units. AI-generated models are usually around a metre across, so the converter scales them to a height you choose (100 mm by default). Turn that off to keep the real size.

Will colours and textures be kept in the 3MF?

No. This converter writes plain 3MF meshes without colour. For a full-colour print, keep the GLB and colour it in your slicer, or export to OBJ with its texture.

Is the model watertight and printable?

The converter keeps the shape exactly; it doesn't repair it. Slicers fix small holes automatically. For meshes with many open edges, run them through your slicer's repair or Blender's 3D Print Toolbox first.

Can I make a 3D model from a photo instead?

Yes. PhotoGenius turns a photo or a text prompt into a textured GLB with Rodin Gen-2.5, Rodin Gen-2.5 Fast, Tripo H3.1, TRELLIS.2, Rodin Gen-2 or Hunyuan3D 3.1, which you can then convert here. See Image to 3D model.

Turn a photo into a 3D model

Rodin Gen-2.5, Rodin Gen-2.5 Fast, Tripo H3.1, TRELLIS.2, Rodin Gen-2 or Hunyuan3D 3.1 builds a textured GLB from one image. The price shows before you run it.

Make a 3D model About the 3D generator