What is CLS by connection type
CLS by connection type shows Cumulative Layout Shift (CLS) value broken down by the user’s estimated network quality at the time of page load. This helps you understand if layout shifts are worse for users on slower or unstable connections.
The connection type is based on the browser’s real-time measurements of latency and download speed — not just Wi-Fi vs. mobile data.
Only connection types with traffic during the selected period are shown.
Reported type | What it actually means |
5G | Very fast and low latency — often strong Wi-Fi, Ethernet, or 5G |
4G | Good performance — typical for stable Wi-Fi or solid mobile data |
3G | Moderate speed — may include higher latency or slower downloads |
2G | Poor speed — expect noticeable delays, especially for heavy content |
Slow 2G | Very constrained connection — suitable only for lightweight pages or fallback content |
Healthy CLS by connection type sample
In a healthy case, CLS remains green across 5G and 4G. Slight increases on slower networks are acceptable — but layout shifts should always stay within the 'good' range.
Unhealthy CLS by connection type sample
If even users on fast connections (4G, 5G) experience layout shifts, it’s not the network — it’s your layout. Content shifting late due to fonts, ads, or lazy-loaded elements often causes poor CLS.
Resolving unhealthy CLS by connection type
Go-to action plan to resolve an unhealthy CLS by connection type:
Ask Uxi to analyze your CLS by connection type values and suggest improvements
Use Filters for affected connection types and examine related CLS lenses for overlapping issues.
Simulate CLS of the suspected lens to see if fixing it will resolve the CLS by connection type. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by connection type values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
Try it yourself
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