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cadformats.com/convert/stl-to-glb

.stlSTL→.glbGLBlossless

Convert STL to GLB

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

Drop your .stl file

up to 250 MB · .stl

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

Destroyed

  • A recorded unit: GLB stores none

↺ the reverse: GLB → STL · about .stl · about .glb · just view it instead

Why people convert STL to GLB

For showing a mesh on the web or in AR, or getting it into Blender or a game engine as one clean file.

The geometry passes through unchanged. The scale doesn't. STL is unitless and read as millimetres, GLB is metres, so coordinates are divided by 1000. This site does that automatically, which is why the model shows up at a sensible size in a web viewer instead of a kilometre wide.

What you get

You get a binary GLB file containing the same triangles the STL 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.

The conversion runs in your browser. Your file stays on your computer and is not uploaded.

What to check afterwards

  • STL carries no unit. The numbers in the file are just numbers, so the conversion assumes millimetres. Check the overall dimensions of the result before you commit to machining or printing it. A file exported from a package set to inches will be 25.4 times out.
  • The numbers change. GLB is read in metres and STL 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 STL carries, so the main reason to choose a different target is what the receiving software accepts.

Going the other way

Convert GLB back to STL. 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 9 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.