A system calibrates one or more sensors mounted to an autonomous vehicle. From the one or more sensors, the system identifies a primary sensor and a secondary sensor. The system determines a reference angle for the primary sensor, and based on that reference angle for the primary sensor, a scan-start time representing a start of a scan and a scan-end time representing an end of a scan. The system receives, from the primary sensor, a primary set of scan data recorded from the scan-start time to the scan-end time. The system receives, from the secondary sensor, a secondary set of sensor data recorded from the scan-start time to the scan-end time. The system calibrates the primary and secondary sensors by determining a relative transform for transforming points between the first set of scan data and the second set of scan data.