What is MTTD (Mean Time To Detect)?

Definition

MTTD measures the average time between a failure occurring and the team becoming aware of it. It is the gap between when something breaks and when someone knows it is broken.

A low MTTD means your monitoring and alerting systems are working well. A high MTTD often means you are learning about outages from customer complaints instead of your own tools. That is a sign your monitoring has gaps.

MTTD is the first phase of any incident. It feeds directly into MTTR — you cannot start repairing something you do not know is broken. Reducing MTTD is often the highest-leverage improvement a team can make.

Why it matters

Every minute of undetected downtime is a minute where users are affected and no one is working on a fix. MTTD is often the largest component of total incident duration, especially for teams using slow monitoring intervals.

A 5-minute check interval means your MTTD can never be less than 5 minutes in the worst case, and averages around 2.5 minutes even for instant failures. With 30-second checks, that worst case drops to 30 seconds.

How Uptrack helps

Uptrack's 30-second check intervals minimize MTTD by design. When a service goes down, the next check detects it within 30 seconds. A confirmation check runs immediately after, and the alert is sent within a minute of the failure.

This is 10x faster than tools that check every 5 minutes, turning what could be minutes of silent downtime into near-instant detection.