Optimizing Core Web Vitals with Lighthouse, CrUX Insights, and Real User Metrics (RUM) for Better SEO Performance
Core Web Vitals (CWV) are crucial for both user experience and search rankings. Optimizing these metrics can significantly boost your website’s performance, engagement, and organic traffic. But how do you dig deeper into CWV data to pinpoint the exact issues and take action? In this post, we’ll guide you through how to segment data for more actionable insights and improve Core Web Vitals by focusing on device type, connection speed, and country-level segmentation.
1. Understanding Core Web Vitals (CWV) Segmentation
Core Web Vitals consist of three key metrics that measure how users experience a web page:
LCP (Largest Contentful Paint): Measures how long it takes for the largest visible content element (like an image or text block) to load.
CLS (Cumulative Layout Shift): Measures visual stability, i.e., how much the page layout shifts while loading.
INP (Interaction to Next Paint): Tracks the time it takes for a page to respond to user input, such as clicks or typing.
While improving these metrics is important for every website, not all users experience them the same way. This is why segmenting CWV data is crucial. By focusing on user experience across different device types, connection speeds, and even countries, you can identify where the biggest issues lie and prioritize your efforts.
2. Segmenting Data by Device Type and Connection Speed
Segmenting by Device Type:
Devices play a significant role in user experience. A page that performs well on a desktop may not necessarily offer the same experience on mobile, especially when it comes to Core Web Vitals. By segmenting CWV data by device type (mobile vs. desktop), you can pinpoint specific areas for improvement.
Mobile: Mobile-first indexing and mobile optimization are critical for user experience. If your mobile version has a high LCP or poor CLS scores, it’s important to optimize the mobile experience.
Desktop: While desktop devices generally perform better in terms of CWV, this doesn’t mean there’s no room for improvement. If you’re seeing high TTFB (Time to First Byte) or other issues on desktop, it could be a sign that the site’s code, images, or server needs optimization.
Segmenting by Connection Speed:
Connection speed, particularly in areas with slower internet, can impact how users experience your website. Here’s how to approach it:
4G Issues: 4G users generally experience a decent loading speed, but if there’s an issue, it could be related to large media files or unoptimized resources like JavaScript.
3G Connections: Slower 3G speeds often drag down CWV scores significantly. If your site is not optimized for slower connections, you may experience poor LCP and CLS scores, which can hurt both user experience and rankings.
Country-Level Segmentation:
For websites with a global audience, country-specific performance is a crucial factor. Google’s CrUX stores country data, which can be accessed through BigQuery. Segmenting by country allows you to pinpoint performance issues unique to different geographical locations. For example, users in countries with slower internet speeds or those accessing your site via older devices may experience poor Core Web Vitals, which you need to address to improve global user experience.
3. Curating CrUX Data to Prioritize Improvements
Before presenting Core Web Vitals issues to your development team, it’s essential to curate and prioritize the data. Here’s how you can do that effectively:
What Needs Fixing:
Start by identifying which metrics are underperforming. Whether it's LCP, CLS, or INP, isolate the pages and elements contributing to poor scores. This might involve looking at:
JS and CSS Files: These can be culprits of slow loading times, especially when there’s unused or unnecessary code that’s blocking the rendering process.
Render-Blocking Resources: Identify any resources that are preventing the page from loading as quickly as it should, such as heavy JavaScript or large images.
Which Users Are Experiencing Low CWV Scores:
Once you know what needs fixing, the next step is to identify which users are most affected by the issues. This involves segmenting by:
Device Type: Mobile users are typically more affected by slow loading times and layout shifts due to the smaller screen size and different browsing behaviors.
Connection Speed: Users on 3G or slow 4G connections are likely to experience the most significant issues with CWV scores.
Country: If specific countries are seeing lower scores, this can help you identify region-specific issues related to server locations or regional internet speeds.
4. Tools to Help Analyze and Fix Core Web Vitals Issues
Several tools can help you dig deeper into the issues affecting Core Web Vitals, enabling you to identify root causes and take actionable steps. Here are some useful tools for analyzing CWV data:
Google PageSpeed Insights’ Tree Map (Tool #1):
This tool allows you to find JavaScript files with unused code. Unused JS can slow down the page’s loading time and increase LCP, so identifying and removing these files can make a big difference. However, note that some JavaScript may be used upon interaction (e.g., for dynamic content), and this can’t always be removed.
WebPageTest.org:
WebPageTest.org lets you test your page’s speed and performance. It also gives you detailed reports about how long different elements take to load. If your page has unoptimized JS or CSS, this tool can help identify which files are contributing to slow load times.
PageSpeed Insights:
PageSpeed Insights helps you find the items contributing to high CLS, LCP, and other performance issues. It offers actionable insights on how to optimize images, JavaScript, and CSS files, as well as suggestions to improve server response time.
Performance Insights:
This tool helps identify root causes of common performance issues, like high TTFB (Time to First Byte), render blocking, and layout shifts. It breaks down exactly where improvements can be made.
Lighthouse:
Lighthouse provides detailed audits of your page, including Core Web Vitals scores. It allows you to see how CWV metrics change when interacting with the page, helping you pinpoint performance issues that may not be obvious at first glance.
Web Vitals Extension:
This browser extension lets you view Core Web Vitals metrics directly in Chrome. It's perfect for quickly checking how your site performs under real user conditions, and you can use it alongside Chrome DevTools to dig into the technical details.
Curated Real User Metrics (RUM):
RUM data is essential for understanding how users experience your site in the real world. Segment this data by:
Page
Device Type
Connection Speed
and analyze it for Pass/Fail Scores and Organic Ranking Lift Opportunities.
5. Key Takeaways for Optimizing Core Web Vitals
Segment CWV Data: Understand which metrics need improvement by segmenting data by country, template, subfolder, device type, and connection speed. This segmentation will allow you to focus on the areas that matter most.
Curate Data: Before presenting issues to development, curate CrUX data to understand what needs to be fixed and which users are experiencing poor CWV scores. This will help developers know where to focus their efforts.
Monitor Performance After Fixes: After implementing improvements, keep monitoring CWV scores for the affected segments. This helps ensure that the changes made positively impact the user experience and your search rankings.
Focus on Biggest Opportunities: Prioritize URLs with the biggest potential to improve organic rankings. Use tools like PageSpeed Insights and Lighthouse to diagnose and fix the most pressing issues.
Conclusion: Laser-Focused CWV Optimization
Improving Core Web Vitals requires a targeted approach. By segmenting CWV data by device type, connection speed, and country, you can identify where the biggest issues are and focus your efforts on resolving them. Tools like PageSpeed Insights, WebPageTest.org, and Lighthouse give you the insights you need to troubleshoot and optimize your pages effectively. The goal is to ensure that your website performs well for every user, regardless of their device or internet connection, leading to better rankings and an improved user experience.
About RSC Digital Marketing
At RSC Digital Marketing, we specialize in helping businesses improve their website performance through data-driven SEO strategies. If you’re struggling with Core Web Vitals or other technical SEO challenges, contact us for a comprehensive audit and actionable solutions to boost your site’s performance.
