Are my files uploaded to a server?

No. This conversion runs inside your browser using your own device’s processing power, and the file is not uploaded. Once a tool has been used once (video, text recognition and background removal download their engine from this site the first time), it keeps working when your connection drops.

Can I print it straight away?

You can slice it straight away. Whether it prints well depends on the model — wall thickness, overhangs and whether the mesh is watertight are properties of the model, not of the conversion.

What happens to the colours?

They are not in the STL, because STL cannot store colour. Every STL is like this, from every program.

Convert GLB to STL

Runs on your device · Your file never leaves your device.

You have a GLB — downloaded, exported from a web tool, or handed to you — and you want to print it. STL is what the slicer wants. This takes the shape out of the GLB and writes it as a binary STL.

Everything that is not shape stays behind, because STL has no room for it: colours, textures and any animation. What you get is the geometry, in the format 3D-printing slicers expect. If the GLB held several separate objects they are written into the one STL together, exactly as they sat relative to each other.

The conversion runs on your own machine, which for a 3D file is the whole point: a model is usually a client’s product, a scanned property or something not yet announced. Nothing is sent to a server, so there is nothing to delete afterwards and nothing to take anyone’s word for.

How to convert GLB to STL

Drop the GLB file — and its companion files if it has any.
Check that STL is selected.
Press Convert.
Download the STL file.

Supported formats and limits

Input: GLB
Output: STL
Companion files: None — the GLB carries everything
Keeps animation: No — the format cannot store it
Where it runs: In your browser; the model is never uploaded

Not for: Mending a mesh for printing — holes, flipped faces and non-manifold edges come through as they were.

What goes into the STL

Every mesh in the GLB is written into the one STL, each at the place, angle and size it has in the scene. A rigged character is written in the pose its bones hold in the file, not in any frame of its animation, and shape keys (morph targets) stay at the base shape. Points and lines are left out, because an STL can only hold triangles.

The normals stored in the GLB are not copied. Each triangle's facing direction is worked out again from the order of its three corners, so a triangle whose corners run the wrong way faces inwards in the STL. GLB files compressed with Draco or meshopt open normally, and a part repeated by instancing is written once for every copy.

The size in the slicer

A GLB counts in metres. An STL stores no unit, and slicers read its numbers as millimetres, so the tool multiplies every number by 1000 on the way: a figure 1.7 metres tall is 1700 in the STL and arrives in the slicer at its real size. The page shows that size in millimetres before you convert.

Which way is up

GLB is built with Y as the up direction, while slicers build upwards along Z. The tool gives the model a quarter turn, so a figure that stands upright in a web viewer also stands upright on the print bed. If you would rather keep the axes as they are, choose that on the page before converting.

Frequently asked questions

Are my files uploaded to a server?: No. This conversion runs inside your browser using your own device’s processing power, and the file is not uploaded. Once a tool has been used once (video, text recognition and background removal download their engine from this site the first time), it keeps working when your connection drops.
Can I print it straight away?: You can slice it straight away. Whether it prints well depends on the model — wall thickness, overhangs and whether the mesh is watertight are properties of the model, not of the conversion.
What happens to the colours?: They are not in the STL, because STL cannot store colour. Every STL is like this, from every program.