SketchUp to STL without SketchUp Pro or an extension
STL export in SketchUp needs the desktop version and, depending on the version, an extension
from the Extension Warehouse. Here you upload the .skp file and get an STL ready for a slicer
such as Cura, PrusaSlicer, Bambu Studio or Chitubox.
Size and orientation
SketchUp models are drawn to real size and stored in inches, whatever units the model shows. The STL is written in millimetres by default, so a part drawn 40 mm wide arrives 40 mm wide in the slicer; you can choose centimetres, metres, inches or feet instead. The Z axis points up, as in SketchUp and in every slicer, so the model stands the way you drew it.
What goes into the STL
Every component and group is placed where it is in the model, nested components included, and each copy of a component is included once per placement. Faces are triangulated, holes in faces stay open, and faces that are painted on both sides are written once. Loose edges and guides, which have no surface, are left out: an STL holds only triangles.
Getting a good print
An STL prints well when the model is a closed solid. SketchUp doesn't enforce that, so check in your slicer whether the mesh is reported as manifold, and use its repair function if it isn't. Very small details (under about 1 mm, the size SketchUp itself struggles to draw) may need to be scaled up in SketchUp first; a common trick is to draw at 1000 times the size, then pick metres here so the STL comes out at the right size.
Other formats in the same upload
The same job gives you OBJ with materials and textures, GLB, and a SketchUp 2017 copy of the model; DXF and PLY are under "More options". The file can be from any SketchUp version, from SketchUp 3 to 2026, and it can even be damaged: what is readable is exported, and the result page says what was missing.
More about what this tool reads and writes: SketchUp File Repair and Converter (SKP to 2017, STL, OBJ).