Having trouble uploading submission

Hello! Sorry if this is a silly question. On blender, my mesh looks pretty simple. But when I upload it to SketchFab, it shows as being very dense and made of triangles instead of the quads I put together.

I tried uploading as a .blend and a .stl, and applied the modifiers before exporting. 

Thanks for your help!

  • Vue Thao(euv) replied
    Have you tried saving it as .fbx format?