What is CLS by UTM Medium
CLS by UTM Medium shows Cumulative Layout Shift (CLS) values across different UTM mediums (e.g., see_pricing_options). This lens helps you understand which campaign mediums are delivering a visually unstable experience to users — potentially hurting trust and engagement.
The list only includes UTM mediums that generated traffic to your site during the selected period.
Layout shifts may vary between mediums depending on how landing pages are structured, what assets are loaded dynamically, or what third-party scripts are triggered.
Healthy CLS by UTM Medium sample
A healthy CLS by UTM medium lens shows all green — meaning traffic from your marketing mediums is loading with stable layouts across the board.
Some variation is expected, but as long as none show yellow or red, your campaign experience is visually consistent.
Unhealthy CLS by UTM Medium sample
In the example below, multiple UTM mediums show poor CLS. This signals that specific traffic sources may be arriving on unstable layouts — possibly due to campaign-specific landing pages or banners loading late.
Common causes include:
Medium-specific overlays or modals being injected too late.
Custom content blocks or layout changes based on query parameters.
Ads, fonts, or embeds shifting visible content after initial render.
When layout shifts impact campaign traffic, conversion suffers — especially on mobile.
Resolving unhealthy CLS by UTM Medium
Go-to action plan to resolve an unhealthy CLS by UTM Medium:
Ask Uxi to analyze your CLS by UTM Medium values and suggest improvements
Use Filters to isolate unstable traffic segments, then compare with other CLS lenses (e.g., by page, country, or device).
Simulate CLS of the suspected lens to see if fixing it will resolve the CLS by UTM Medium. If yes, this is where the resolution focus should be.
Use an automated CLS optimization tool like Navigation AI to improve your CLS by UTM Medium values
Once you’ve improved CLS, set an alert to be the first to know if it starts worsening again.
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