Work out alert noise ratio instantly with clear inputs, formula shown and shareable results.
The actionable rate is the metric that determines whether alerts are trusted. Google's SRE guidance is that every page should be actionable, novel and urgent; when the actionable rate falls below roughly half, responders start closing alerts without investigating, and the monitoring system stops functioning as a detection mechanism regardless of its coverage.
Alert quality
noise ratio = (total - actionable) / total; wasted time = noise count x minutes per alert
Above 80 percent for anything that pages. Alerts that are merely informative belong on a dashboard or in a ticket queue, not on a phone at 3 am.
Raise thresholds to symptom level rather than cause level, alert on burn rate against an SLO instead of on raw metrics, and group related alerts into a single incident.