Question 1

Are my 3D models uploaded anywhere?

Accepted Answer

No. Loading, viewing, diagnosis and repair run entirely in your browser or on your device — there is no server that ever receives the model file.

Question 2

Which file formats are supported?

Accepted Answer

Viewing: STL, OBJ (with MTL and textures), GLB, glTF and ZIP archives containing gltf+bin/textures. Draco- and Meshopt-compressed GLB files are decoded automatically. USDZ is not displayed but generated: every model can be exported as a true-scale USDZ for AR Quick Look.

Question 3

What is the difference between Free and PRO?

Accepted Answer

Free includes the complete viewer with every print diagnostic (open edges, watertightness, wall thickness, material estimate) and no limits. PRO unlocks the repair engine, the print-bed fit check, print-ready STL/3MF exports and watermark-free images. In short: diagnosis is free, fixing is paid.

Question 4

What does the repair engine fix — and what doesn't it (yet)?

Accepted Answer

It fills holes, flips wrongly oriented normals and removes degenerate triangles — the most common reasons a slicer rejects an STL. Self-intersections and hollowing models are not included yet.

Question 5

Can I use this from CI or an AI agent?

Accepted Answer

Yes. The same engine also runs as a command-line tool and as an MCP server for AI agents — offline, no upload, with machine-readable JSON and diagnostic codes instead of prose. Nothing to install: npx -y 3dviewer-cli check model.stl. In a pipeline the run ends with an error exit as soon as a model has defects. The print check is just as free there; repair and print-ready export need a PRO licence.

Question 6

Is there an app as well?

Accepted Answer

Yes, a native iOS app with the same features is in preparation. A web purchase can also be unlocked in the app via a redemption link/QR code — no account needed.