Open the model on 0xr.space, press More in the dock, then Info. A panel called Model information lists POLYGONS, PARTS / NODES, MATERIALS, TEXTURES and SIZE, with AUTHOR, LICENSE, SOURCE and FORMAT above them and VOLUME and WATERTIGHT below. It works in a browser, on an Android phone and in VR on Meta Quest, with nothing to install.
POLYGONS counts triangles, written short, like ~1.2m tris, so a quad counts as two. SIZE is the model's own bounding box, in millimetres under a metre and in metres above. AUTHOR and LICENSE read Unknown and N/A when nothing is known about the file. Info is not offered for Gaussian splats or point clouds.
Triangles. Every format is read into triangles, so the count matches what a game engine would draw, not the quad count in a modelling tool.
Parts are the nodes that carry a mesh; nodes are every node in the scene, empty groups included.
No author came with the file. Most imported files show Unknown and N/A.
No. It is read on the device, and nothing is sent to a server unless you create a share link yourself.