Mean Time To Repair (MTTR) is a metric used to measure the average time it takes to repair a failed component or system. It is used to measure the efficiency of maintenance operations and management, and is calculated by dividing the total time spent on repairs by the number of repairs completed. MTTR is an important metric for maintenance operations and management, as it helps to identify areas for improvement and ensure that repairs are completed in a timely manner. MTTR is often used in conjunction with Mean Time Between Failure (MTBF) to measure the reliability of a system or component. CMMS software can be used to calculate MTTR.