Alerts & Notifications

    Response Time Threshold Alerts

    Get alerted when response times consistently exceed your limits.

    Updated 2026-03-23
    2 min read
    response time
    threshold
    performance

    Response Time Threshold Alerts#

    Set a per-site millisecond threshold. When response times exceed it for 2+ consecutive checks, you get a slow_response alert. Use this to catch performance degradation before it becomes downtime.

    Setup#

    Go to Edit Site → Advanced Monitoring → set Response Time Threshold (e.g., 2000ms). Save. The threshold applies from the next check onward and does not affect historical data.

    How It Works#

  1. Response time is measured on every uptime check across all monitoring regions
  2. 2 consecutive threshold breaches trigger an alert (single spikes are ignored)
  3. The alert is delivered through all channels configured on the site
  4. A recovery notification fires when response times return below the threshold for 2 consecutive checks

    5. Choosing a good threshold#

    Look at your last 30 days of response time history in the Performance tab. Set the threshold at roughly your p95 — high enough to avoid noise from normal variance, low enough to catch real degradation. Marketing sites typically use 2000-3000ms; API endpoints 500-1000ms.

    Related settings#

  5. Response degradation alerts — rolling-average baseline instead of a fixed threshold. Better for sites with variable traffic patterns.
  6. Performance budgets — page-level Core Web Vitals limits, separate from uptime response time.

    7. FAQ#

    Does the threshold affect uptime %?

    No. The site is still considered "up" as long as it returns a 2xx status code. The threshold only controls the slow_response alert channel.

    Can I set different thresholds per region?

    Not yet — the threshold is global per site. Vote for it on the roadmap.

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