Roughness Log

Your phone already has the sensors the commercial survey platforms use: a three-axis accelerometer and GPS. This reads them in the browser. No app, no account, no subscription.

Three things it is not.
1. It is not IRI. Real International Roughness Index comes from a calibrated profile run through a quarter-car simulation. This is the RMS of vertical acceleration — it correlates with roughness but is a different quantity and is calibrated against nothing. Do not put it in a report as IRI.
2. It is not a distress survey. Accelerometers feel unevenness and potholes. They cannot see cracking, ravelling or faded striping. Use the Pavement Change detector for those.
3. It is not comparable between vehicles. Suspension dominates the signal. Readings compare honestly between runs on the same phone in the same vehicle, and not otherwise.