What is TTFB by hour of the day
TTFB by hour of the day breakdown shows how Time to First Byte (TTFB) varies throughout different times of the day.
This breakdown helps you identify whether server response times slow down during peak traffic periods, content refresh windows, or background processing tasks. Since TTFB measures how quickly the server starts responding, tracking it by hour highlights when users may be waiting longer just to see the page begin loading.
TTFB by hour of the day sample
Should you worry
In a healthy view, TTFB remains green and stable across all hours. Minor fluctuations are normal, but none that push values into the yellow or red range.
A healthy setup typically shows:
TTFB consistently under 800ms across the day.
No significant spikes during traffic peaks.
Load-balanced infrastructure and CDN caching working smoothly.
If TTFB remains steady, time of day is not affecting server response performance.
Unhealthy TTFB by hour of the day
If TTFB worsens at certain times, it often signals strain on the backend or infrastructure.
Common causes include:
Traffic surges overwhelming servers or databases.
Cache invalidations causing fresh requests to hit the origin.
Background jobs or cron tasks running at predictable hours and slowing responses.
Third-party bottlenecks delaying dynamic rendering.
These time-based delays make the site feel inconsistent depending on when users visit.
Resolving unhealthy TTFB by hour of the day
Go-to action plan to resolve an unhealthy TTFB by hour of the day:
Ask Uxi to analyze your TTFB by hour of the day values and suggest improvements.
Use Filters to isolate problem hours by device, region, or traffic source.
Simulate TTFB of the suspected breakdown to see if fixing it will resolve the TTFB by hour of the day. If yes, this is where the resolution focus should be.
Use an automated optimization tool like Navigation AI to improve your TTFB by hour of the day values.
Once you’ve improved TTFB, set an alert to be the first to know if it starts worsening again.
Try it yourself
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