What Role Does Ad Placement Play in Causing "CLS Issue: More Than 0.1 (Mobile)," and How Can I Prevent Content Shifts Due to Ads?


Ad placement significantly contributes to "CLS Issue: more than 0.1 (mobile)" in terms of causing significant content shifts while loading. Addressing CLS (Cumulative Layout Shift) means creating a stable visual experience for the user by ensuring ads don't lead to unexpected layout changes. Preventive measures include reserving space for ads, evaluating ad network impact, and employing ad loading strategies that minimize noticeable content shifts.

Understanding the Role of Ad Placement

Impact on Cumulative Layout Shifts (CLS)

Ad placement impacts CLS when ads dynamically load and change the content layout without warning, creating an unpredictable and frustrating user experience. In mobile view, these shifts can be even more disorientating due to smaller viewport sizes [Cumulative Layout Shift (CLS), 2020].

Evaluating Ad Networks and CLS

Some ad networks might be more prone to causing layout shifts due to the nature of their ad loading strategies. Choosing networks that prioritize stability or employing strategies that minimize content shifts can be part of a solution line [Ad Speed, 2021].

Preventing Content Shifts Due to Ads

Reserving Space for Ads

Allocating appropriate space for ads on a webpage before they load can help prevent unexpected layout shifts. One strategy is to use the 'aspect-ratio' CSS property to reserve space on the page that matches the expected size of the ad [Aspect Ratio, 2021].

Optimizing Ad Loading Strategies

Implementing ad loading strategies that prioritize user experience can limit disorientating content shifts. This might include loading ads during idle times, using 'lazy loading' for ads not immediately visible, or progressively loading ad contents [Native Lazy Loading for the Web, 2020].

Monitoring CLS with Web Vitals

Continuous monitoring of CLS and other Core Web Vitals allows for proactive issue detection and remediation. Tools like Google's PageSpeed Insights, Lighthouse, and Search Console can assist in identifying and addressing CLS issues [Web Vitals, 2020].


Preventing content shifts due to ad placements involves understanding the causes, setting aside space for ads, optimizing their loading strategies, and constant monitoring. These steps enhance the user experience, improve page stability, and mitigate CLS issues.