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cadformats.com/convert/3mf-to-glb

.3mf3MF→.glbGLBlossless

Convert 3MF to GLB

Convert 3MF to GLB in your browser. The conversion runs on this page and the file never leaves your computer.

Drop your .3mf file

up to 250 MB · .3mf

Free, and it opens in this tab. Nothing is uploaded, and there's no account to make.

Runs locally · nothing uploaded

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
  • Colour
  • Separate parts and their positions

Destroyed

  • A recorded unit: GLB stores none

↺ the reverse: GLB → 3MF · about .3mf · about .glb · just view it instead

Why people convert 3MF to GLB

Putting a print file on the web, which is what a print service, a model marketplace or a maker's portfolio needs in order to show a preview.

3MF and GLB have more in common than their audiences suggest. Both hold colour and both keep separate parts with their positions, so a multi-part model with coloured components arrives in a browser viewer looking as it does in a slicer.

The numbers change. 3MF declares its unit, so the conversion knows exactly what it has, and everything is converted into glTF's metres. A 50 mm part becomes 0.05, which is right and looks wrong the first time you see it in the JSON.

What you get

You get a binary GLB file containing the same triangles the 3MF 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.

The output uses metres, as required by the glTF specification.

Carried across: 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

  • 3MF declares its unit in the file. Check the output dimensions in the receiving application, especially when its import settings can override the unit.
  • The numbers change. GLB is read in metres and 3MF in millimetres, so every coordinate is rescaled. The result is the same physical size, but the numbers in the file are different numbers.
  • Coordinates are stored as 32-bit floats. For a part measured in millimetres that's far finer than any machine tolerance. For a model spanning hundreds of thousands of units it isn't.

If you need something this conversion cannot give you

This pair loses very little. GLB carries what 3MF carries, so the main reason to choose a different target is what the receiving software accepts.

Going the other way

Convert GLB back to 3MF. 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 13 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.