I vibe-coded a single-file HTML tool that lets you upload a floor plan image, calibrate it with one known dimension, then draw measurement lines anywhere. Shows feet/inches and meters. Touch-friendly with pinch-to-zoom, two-finger pan, and a magnifier loupe for precise endpoint placement. Save multiple sessions to localStorage. No backend, no install.

Useful for checking if your furniture will fit, planning renovations, or just figuring out how far the fridge is from the couch when all you have is a developer's floor plan