Free tool

Online STL viewer

Open STL, OBJ, 3MF, PLY or GLB. Check size, triangles and volume before you slice.

Runs in your browser. Nothing is uploaded.

How to use it

1Open a file
Drop an STL, OBJ, 3MF, PLY or GLB, or try a sample. Nothing is uploaded.
2Look around
Drag to orbit, scroll or pinch to zoom, right-drag to pan. Toggle wireframe, the plate grid and auto-rotate.
3Check measurements
Read the X, Y and Z size in millimetres or inches, triangle count, volume, surface area and the weight in PLA.
4Save a screenshot
Download a PNG of the current view for a listing, a client or your notes.

Numbers worth checking before you print

Size: catches files exported in inches or metres.
Volume and weight: estimates filament use and cost.
Triangles: a very heavy mesh slows slicing; a very light one may look faceted.

If a mesh looks broken, open it in your slicer or MeshLab to repair it. For 3MF files you want as STL, use the 3MF to STL converter.

Questions

Which file formats does it open?

STL (binary and ASCII), OBJ, 3MF, PLY and GLB.

Is it a replacement for Microsoft 3D Viewer?

For viewing and measuring print files, yes. Microsoft removed 3D Viewer from the Store on July 1, 2026, and this viewer works in any modern browser on Windows, Mac, Linux and phones.

How accurate is the volume?

Exact for closed, watertight meshes. Open meshes have no true inside, so their volume is an approximation.

Why does my model look sideways?

Print files are usually Z-up and many other 3D files are Y-up. Toggle Z axis is up to fix the orientation.