Table of Contents
- What is Cumulative Layout Shift (CLS)?
- Measuring CLS in Google Search Console
- Common Causes of CLS Issues
- Practical Strategies to Fix CLS Problems
- Monitoring and Maintaining Good CLS Scores
- Conclusion
- FAQ
Have you ever experienced the frustration of clicking a link only to have the content jump before your eyes? This common issue, known as Cumulative Layout Shift (CLS), can significantly disrupt user experience on your website. As digital marketers and webmasters, we know that user experience is paramount, and understanding CLS is vital for maintaining a user-friendly site. In this post, we’ll delve into what CLS is, how it affects your website’s performance, and actionable steps we can take to improve it.
With the rise of Core Web Vitals as crucial ranking factors, Google has shifted its focus towards user experience metrics, and CLS is one of the key components. According to Google, a good CLS score is crucial for providing a seamless browsing experience, and it’s important that we understand how to measure and optimize it to enhance our website’s performance.
In this blog post, we will explore the following topics:
- What CLS is and why it matters
- How to measure CLS using Google Search Console and other tools
- Common causes of CLS issues
- Practical strategies to fix CLS problems
- Monitoring and maintaining a good CLS score
By the end of this post, we will have a comprehensive understanding of CLS and how to tackle this issue effectively. Let’s embark on this journey together to enhance our websites and ensure we provide the best possible experience for our users.
What is Cumulative Layout Shift (CLS)?
Cumulative Layout Shift (CLS) is a metric that quantifies the unexpected shifting of web page content during its loading phase. It measures the visual stability of a page, ensuring that users don’t have to deal with content that moves around unexpectedly. Each time a visible element changes its position, it counts as a layout shift, which contributes to the cumulative score.
Why Does CLS Matter?
CLS is one of the three Core Web Vitals metrics introduced by Google, alongside Largest Contentful Paint (LCP) and First Input Delay (FID). These metrics are essential for evaluating the overall user experience on a website. A high CLS score can lead to user frustration, missed clicks, and ultimately, increased bounce rates. For instance, if a user tries to click a button that suddenly shifts position, they may end up clicking the wrong link or button instead.
A good CLS score is considered to be 0.1 or less, while a score above 0.25 is deemed poor. Google uses these scores to rank websites, so understanding and optimizing CLS can directly impact our search visibility.
Measuring CLS in Google Search Console
Google Search Console provides a comprehensive platform for monitoring various aspects of your website’s performance, including CLS. Here’s how we can check our CLS metrics:
- Access Google Search Console: Log in to your Google Search Console account and select the property (website) you want to analyze.
- Navigate to Core Web Vitals: In the left-hand sidebar, locate the “Core Web Vitals” report. This section gives us an overview of how our site performs concerning the three Core Web Vitals metrics.
- Review CLS Scores: Here, we can see the percentage of URLs that pass the Core Web Vitals assessment, specifically focusing on CLS. URLs are categorized into “Good,” “Needs Improvement,” or “Poor.”
- Drill Down into Details: By clicking on the “Open report” link, we can see detailed performance metrics for mobile and desktop versions, identify specific pages with CLS issues, and understand the extent of the problem.
- Analyze the Causes: Google Search Console also provides insights into what may be causing CLS issues, allowing us to address specific elements that are contributing to the score.
Other Tools for Measuring CLS
While Google Search Console is invaluable, there are additional tools and methods we can utilize to measure and analyze CLS:
- Lighthouse: This automated tool provides a detailed report on performance, accessibility, best practices, and SEO. By running a Lighthouse audit, we can get insights into CLS and other performance metrics.
- Web Vitals Chrome Extension: This handy browser extension allows us to view real-time performance metrics, including CLS, as we browse our site.
- Real User Monitoring (RUM): Tools like Google Analytics can provide real user data which helps in understanding how actual users experience layout shifts on our website.
Common Causes of CLS Issues
Understanding the causes of CLS issues is crucial for implementing effective fixes. The most common culprits include:
1. Images Without Defined Dimensions
When images load without specified width and height attributes, the browser cannot allocate space for them until the image fully loads, leading to unexpected shifts.
2. Dynamically Loaded Content
Content that loads after the initial render, such as ads, widgets, or AJAX calls, can push other content around, resulting in layout shifts.
3. Font Loading Issues
Web fonts can cause shifts if their size is different from fallback fonts. When the web font loads, text may reflow, resulting in a layout shift.
4. Third-Party Elements
Scripts or iframes from external sources (like ads or social media widgets) can resize or load content dynamically, causing layout changes that users don’t expect.
5. Responsive Design Issues
Websites that are not optimized for responsive design may experience shifts as elements resize or rearrange themselves based on the viewport size.
Practical Strategies to Fix CLS Problems
Now that we understand what causes CLS issues, let’s discuss actionable strategies to mitigate them effectively:
1. Assign Fixed Sizes to Images and Videos
By explicitly defining the width and height attributes for images and videos, we can ensure that the browser allocates the correct amount of space before these elements load. This simple step can drastically reduce layout shifts.
<img src="example.jpg" width="600" height="400" alt="Example">
2. Use Placeholders for Dynamic Content
When dynamically loaded content (like ads) is inserted, it can shift existing content. To prevent this, use placeholders with fixed dimensions to occupy space until the content loads.
<div style="min-height: 200px;">Loading...</div>
3. Optimize Web Font Loading
To reduce font-related shifts, consider preloading web fonts. This allows the browser to download fonts sooner, ensuring that the correct font is applied without shifting existing content.
<link rel="preload" href="font.woff2" as="font" crossorigin="anonymous">
4. Monitor and Manage Third-Party Content
Limit the number of third-party scripts and ensure they load asynchronously. If possible, use a loading indicator to reserve space for content that loads dynamically.
5. Utilize CSS Aspect Ratios
In responsive designs, setting an aspect ratio can help maintain the dimensions of elements, preventing layout shifts as the viewport changes.
img {
aspect-ratio: 16/9;
width: 100%;
}
6. Use CSS Transformations for Animations
When animations are necessary, using CSS transitions and transformations can help maintain layout stability while still providing visual updates.
Monitoring and Maintaining Good CLS Scores
Once we implement fixes, continuous monitoring is essential to ensure that our CLS scores remain good. Here are some strategies to keep our scores in check:
1. Regularly Check Google Search Console
Keep an eye on the Core Web Vitals report to track changes in CLS scores. Promptly address any new issues that arise.
2. Use Automated Monitoring Tools
Consider utilizing tools like DebugBear or other performance monitoring services to receive alerts when CLS scores regress or when new issues are detected.
3. Benchmark Against Competitors
Understanding how we stack up against competitors can provide insights into performance. Tools that offer competitive analysis can help us identify areas for improvement.
4. Conduct Periodic Audits
Run regular audits using Lighthouse or similar tools to identify any emerging CLS issues, ensuring that our site remains optimized.
Conclusion
Cumulative Layout Shift (CLS) is a vital metric affecting user experience and, consequently, our website’s performance in search rankings. By understanding what CLS is, measuring it accurately, and implementing practical strategies to mitigate issues, we can significantly enhance our users’ experience and improve our site’s performance.
As digital marketers, it’s our responsibility to ensure that our websites provide a seamless browsing experience. By continuously monitoring and optimizing for CLS, we can stay ahead of the curve in the competitive digital landscape.
If you’re interested in exploring more about digital marketing strategies and enhancing your online presence, we invite you to visit Marketing Hub Daily for more insights and updates. Together, let’s continue learning and improving our marketing expertise!
FAQ
What is a good CLS score?
A good CLS score is considered to be 0.1 or less. Scores above 0.25 are considered poor and can negatively impact user experience.
How can I measure CLS?
You can measure CLS using Google Search Console, Lighthouse, Web Vitals Chrome Extension, and Real User Monitoring (RUM) tools.
What causes high CLS scores?
High CLS scores are typically caused by images without defined dimensions, dynamically loaded content, font loading issues, third-party elements, and responsive design problems.
How can I fix CLS issues on my website?
To fix CLS issues, assign fixed sizes to images, use placeholders for dynamic content, optimize web font loading, monitor third-party content, and use CSS aspect ratios.
Why is CLS important for SEO?
CLS is one of the Core Web Vitals metrics that Google uses to assess user experience. A good CLS score can positively impact your website’s search rankings.
