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OBJ to STL converter

Convert a Wavefront OBJ mesh from Blender, a 3D scanner or a CAD tool into a binary STL ready for slicing, with control over units and up axis.

Convert.obj→ .stlRuns locally

Drop a file here or

.obj · processed on your device, never uploaded

How to use the OBJ to STL

  1. 1Choose an .obj file (the .mtl and textures are not needed).
  2. 2If the model lies on its side, tick "Source is Y-up".
  3. 3Pick the source units so the size matches the real object.
  4. 4Download the STL.

OBJ files from Blender

Blender works in meters by default and exports OBJ with Y up. If your part shows up as a few millimeters across, set the source unit to meters; if it lies flat on its back, tick Y-up. Check the result in the STL viewer before slicing.

Frequently asked questions

How do I convert OBJ to STL?

Choose your .obj file, confirm the units and orientation in the preview, then download the STL. It runs in your browser.

Are textures and materials kept?

No. STL stores only geometry, so .mtl materials, textures and vertex colors are dropped.

Why is my converted model lying on its side?

Many OBJ exporters, including Blender's default, use Y as the up axis, while 3D printers use Z. Tick "Source is Y-up" to stand it upright.

What units are OBJ files in?

OBJ has no unit field. Exports from CAD tools are usually millimeters; from Blender, often meters. Pick the unit that makes the size match the real object.