Mean Time to Repair
Also known as: MTTR
Mean Time to Repair (MTTR) measures the average time between a defect being detected and it being fully resolved — a key indicator of how efficiently a team responds to and fixes known issues, especially critical production incidents.
MTTR and MTTD are often tracked together as a pair — MTTD measures how fast you notice a problem, MTTR measures how fast you fix it once noticed, and together they roughly describe total real-world impact duration from a defect's introduction to its actual resolution.
Teams working to improve MTTR typically invest in things like better rollback tooling, feature flags for instant disabling of a problematic change, and clearer on-call runbooks — the goal being that once a problem is known, the path to actually fixing or mitigating it is fast and well-rehearsed, not improvised under pressure.
