What is CLS by hour of the day
CLS by hour of the day shows how Cumulative Layout Shift (CLS) varies at different times throughout the day.
This breakdown helps you identify whether layout instability is tied to traffic surges, infrastructure strain, or third-party behavior. Since CLS measures unexpected movements of visible content, tracking it across hours highlights if users experience unstable layouts more during peak periods.
CLS by hour of the day sample
In a healthy view, CLS stays green and stable across all hours of the day. Small variations may happen, but none that push values into the yellow or red range.
A healthy setup typically shows:
CLS values consistently below 0.1 across time ranges.
No large spikes during traffic peaks.
Well-optimized caching and rendering pipelines.
If CLS remains low across the day, your layout stability is not dependent on time or load.
Unhealthy CLS by hour of the day
If you see higher CLS values at specific hours, it often indicates system or third-party strain during certain periods.
Common causes include:
Traffic surges overwhelming servers or CDNs.
Cache misses during content refresh windows.
Third-party ads or widgets loading unpredictably at peak times.
Background jobs or tasks delaying rendering during off-hours.
These time-based instabilities can make the site feel inconsistent depending on when users visit.
Resolving unhealthy CLS by hour of the day
Go-to action plan to resolve an unhealthy CLS by hour of the day:
Ask Uxi to analyze your CLS by hour of the day values and suggest improvements
Use Filters to isolate high-shift hours by device, country, or traffic type.
Simulate CLS of the suspected breakdown to see if fixing it will resolve the CLS by hour of the day. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by hour of the day values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
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