Orbit a model, read its real-world size, and (on a phone) launch true-to-scale AR. If the AR button is missing, your browser is reporting no AR support — check the AR diagnostics panel on the right. Open this page directly in Safari (iPhone) or Chrome (Android) — AR does not work inside in-app browsers (WhatsApp, Instagram, etc.). The default ★ Astronaut uses a USDZ generated by Diorama's ingest CLI — if AR launches on your iPhone, our generator works end-to-end.