MTTDMTTR

MTTDMTTR is a reliability and incident management metric used to evaluate how quickly an organization detects and resolves failures. It is sometimes described as a combined measure of Mean Time To Detect (MTTD) and Mean Time To Repair (MTTR), or as the total time from incident onset to service restoration. Because the two components are defined with different start points, MTTDMTTR is not a universally standardized metric, and definitions vary by organization.

MTTD stands for Mean Time To Detect. It is the average duration between when an incident begins and when it is first identified or acknowledged by monitoring systems, on-call personnel, or users. MTTR stands for Mean Time To Repair (or to Restore). It is the average duration between detection and full restoration of service, including diagnosis, remediation, and verification.

When used as a composite metric, MTTDMTTR can be computed as MTTD + MTTR, representing the average total time from incident onset to restoration. Users should note that this interpretation assumes accurate incident start times and may double-count time if detection is immediate or if start points are inconsistently recorded. In practice, many teams report MTTD and MTTR separately and use MTTDMTTR cautiously as a rough summary of incident duration.

Data for calculation comes from incident timelines in monitoring, alerting, and incident management systems, including timestamps for incident start, detection/acknowledgment, and resolution. Applications include benchmarking, identifying reliability bottlenecks, and guiding process improvements. Limitations include potential inconsistencies in defining incident start, varying severity handling, and the nonstandard nature of the metric across teams.

Best practices to improve MTTDMTTR focus on enhancing detection (better monitoring, alerting, on-call processes) and accelerating repair (runbooks, automation, effective post-incident reviews).