This device/browser doesn't support AR room scanning.
Use Chrome on an Android phone (ARCore-compatible).
Room Scan
Manual: walk to each corner and tap to mark it.
Auto-detect (beta): point at each wall in turn and tap "Capture wall" — its length is read from the camera automatically. Less precise than manual on some phones, so double-check the result before sending.
Walk to each corner of the room and tap "Mark corner" while pointing at the floor point.
Corners marked: 0 · Doors: 0 · Windows: 0
Adjust room shape
Drag a corner to move it, or type an exact wall length below.