Open STL Online

View an STL 3D model in your browser and turn it around with the mouse.

Drop a file here

or

Your file stays on your device.

  • Preview: Good
  • File info: Yes
  • Search: No
  • Editing: No

About STL files

STL is the standard format for 3D printing. It describes the surface of an object as a mesh of triangles, without colours or textures. Slicers, CAD programs and sites like Thingiverse use it.

Open Online draws the mesh with WebGL in your browser. You can rotate, zoom and switch to wireframe, and see the triangle count and the size in model units. The file is not uploaded.

What you can do here

  • Rotate, zoom and move the model with the mouse or by touch
  • Switch to wireframe, hide the grid or darken the background
  • Reset the view with one click
  • See triangles, vertices, size and materials

Limitations

  • Models are shown with simple lighting. Textures and materials are shown for glTF files only.
  • Compressed glTF models (Draco, Meshopt) are not supported yet.
  • glTF files that load extra files from other places are not supported, only self-contained GLB.

Privacy

The file is read by your browser and stays on your device. Open Online has no server that could receive it, and nothing is stored once you close the tab. Privacy policy

Common questions

Are binary and text STL files supported?

Yes. Both encodings are read, and the File info panel tells you which one the file uses.

Why does the model lie on its side?

CAD and printing programs treat Z as up, while most 3D viewers use Y. Open Online starts with Z up for STL files. Turn the “Z axis up” option on or off if the model looks wrong.

What units does the size use?

STL files carry no units. The numbers are in the units the model was made in, most often millimetres.