Core Web Vitals: Definition, Introduction to LCP, FID & CLS, and Core Web Vitals Optimization Tips
March 17, 2021
Prashant Shukla
In 2021, Google kicked things up a notch by introducing Core Web Vitals. Even though “content is still king,” the inclusion of Core Web Vitals as a ranking signal determines how well visitors/users interact with your website.
What Are Google Core Web Vitals?
Core Web Vitals are a set of criteria Google uses to evaluate a website/webpage for determining the overall user experience. Google core web vitals assess your website’s speed, responsiveness, and visual stability alongside existing user experience signals to assess the page experience and user-friendliness.
Core web vitals factors help break down the complex variables so SEO managers and web developers can identify the crucial factors that affect the site’s ranking and user experience.
Businesses should anyway be monitoring these factors because improving the user experience positively impacts the experience a visitor has on the website, which, in turn, can affect their purchasing decision. Think of it from the perspective of adding CTAs, demonstrating information correctly, making the site optimized for SEO, etc.
Why Are Core Web Vitals Important For SEO?
Here are some reasons why core web vitals are important and why they should matter to you:
| Ranking Opportunity |
Beat Close Competitors |
Disrupt The SOV (Share of Voice) |
| It is an excellent ranking opportunity for websites to rank as Google has introduced core web vitals as another ranking signal. |
In the war between two websites with similar content quality and website ranking, page experience can make all the difference. |
Websites that have enjoyed unmatched rankings on Google SERPs may now lose their current ranking to equally competitive websites. If you beat their page experience standards and have excellent content, you can appear at the top of search results. |
Everything considered, it is essential to remember that your page experience score is only one of many important SEO ranking factors that Google uses.
To stay ahead and enjoy a competitive ranking advantage over others, you should keep optimizing your existing SEO strategy and improving the content quality while focusing on core web vitals.
What Are The Three Signals Of Core Web Vitals?
Signal 1: Largest Contentful Paint (LCP): Checks Page Loading Performance
LCP is the first core web vital metric that Google uses to calculate your page experience score.
Largest Contentful Paint or LCP can be defined as the duration it takes for a page on your website to load from a user’s perspective. In simple words, LCP is the time it takes for your user, from clicking on a link to seeing the majority of your website’s content on the screen. The faster your page’s largest element loads, the better your LCP score.
LCP focuses on what truly matters in terms of page speed, i.e., a user’s ability to see and interact with your page without obstruction.
The ideal LCP measurement is 2.5 seconds or faster
Signal 2: Cumulative Layout Shift (CLS): Checks Visual Stability
Cumulative Layout Shift (CLS) measures visual stability. It is a metric that calculates all layout changes not caused by user interaction. If multiple elements on your page move around while the page is loading, the higher your CLS would be. The lower your CLS, the better your page score performance.
A CLS score of less than 0.1 is considered ideal for a webpage.
Signal 3: First Input Delay (FID): Checks Interactivity Responsiveness
First Input Delay (FID) refers to the time it takes for a page to become interactive. You can say that it measures the duration it takes for an activity to occur on a page. More specifically, it measures the time it takes for users to actually do something on your page.
What counts as an interaction? This can include the time it takes a user to choose an option from the menu, enter their email address into a field, or click on a CTA.
The ideal FID measurement is less than 100 ms.
How to Measure Web Vitals Score?
Now that you know what the three core web vitals are, here are some tools to help you measure them to bolster your SEO strategy and increase rankings on search results.
| Tool |
Overview |
Step-by-Step Workflow |
| Google’s Search Console |
Google Search Console comes with a unique core web vitals report under the enhancements section that you can check while conduct a website audit. |
Google Search Console shows you all webpage performance data in one go. |
| PageSpeed Insight |
Google’s PageSpeed Insight shows a web page’s core web vitals alongside valuable advice on improvements you can make. |
After running the audit on the website, you can identify the pages that need work and closely examine the issues on a page using PageSpeed Insights. |
| Lighthouse |
Lighthouse is a Chrome Extension to measure your core web vitals. |
Lighthouse gives you actionable guidance on what actually needs to be fixed to provide a good user experience. It gives you insights on Performance, Accessibility, Best Practices, SEO, and Progressive Web App. |
How to Optimize the Core Web Vitals (LCP, FID, CLS)?
Now that we understand the importance of Core Web Vitals and how to measure them, let’s learn how we can improve them, as per Google guidelines.
How To Optimize Your Website’s LCP:
Minify JS, CSS, and HTML Files:
These core files may contain unnecessary white space, making their size bigger and negatively affecting the site’s performance. Minify JS, CSS, and HTML files by reducing their lines of code.
Optimize Lazy Loading & Large Page Elements:
Lazy loading means a page defers non-critical CSS resources during the initial rendering to make the first-fold content load faster. However, lazy loading, at times, can have a negative effect on LCP as it can lead to unnecessary resource delay. Thus, lazy loading should be done intelligently and with experts’ intervention.
Google’s PageSpeed Insights helps you learn about elements slowing down your page’s LCP. For example, an analysis of Techmagnate’s LCP score on Google’s Page Speed Insights shows up this element as faulty:
Upgrade Your Web Hosting Provider:
Choose a web hosting plan or provider that can meet your site’s specifications, which can increase the web experience as well as the speed. Compare shared environment vs dedicated environment to choose what meets your site requirements.
How To Optimize Cumulative Layout Shift (CLS):
Reserve Space on Your Webpage For Dynamic Content:
Web pages with undesignated space for dynamic content (ads, embeds, and iframes) tend to mess up with the first-fold structure and positioning. This can, sometimes, push up and down the page, resulting in a high CLS and a bad page experience score. Thus, it is important to review the dynamically inserted content and reserve designated for it.
Set Dimensions for Media To Avoid Layout Shift:
Using a set size attribute dimension for media such as videos, images, GIFs, infographics, or other media elements is important. Doing this will show you how much space that element will take up on that page, thus reducing content misplacement on your web page.
Preload Fonts:
Preload Fonts to load the font first when the browser renders the page. This will enable the primary content to load first with no changes or shifts occurring in the layout.
How To Optimize First Input Delay (FID):
Minimize (or Defer) Javascript:
A long JavaScript is a common error causing the main thread to delay. To resolve this, remove them or divide long tasks into smaller, asynchronous ones. At least one task should take under 50 ms.
Compress Non-critical Third-Party Scripts:
Third-party scripts like Google Analytics and heatmaps can negatively impact FID and the content loading speed. Identify the ones that are not crucial for your website and remove/compress them.
Keep Request Counts Low & Transfer Sizes Small:
Optimize code to restrict request counts and minimize transfer sizes of HTML files, media, images etc.
Other Page Experience Factors To Fix:
Here are some other page factors you should optimize to fix and improve the user experience pivotal for boosting your rankings on search results:
Safe Browsing:
Ensure that your website does not contain malicious or deceptive content such as malware. You can refer to Google’s Safe Browsing site status tool to examine your website and learn how safe it is.
HTTPS:
Websites that begin with an HTTPS are more likely to have a secure site connection. You can enable HTTPS on your website through web.dev or upgrade your current hosting plan that includes an SSL certificate.
Mobile-Friendliness:
Check if your webpage is mobile-friendly using Google’s Mobile-Friendly Test. Among other things, improving UX & UI and perfecting off-canvas navigation are the first steps to making your website mobile friendly.
Conclusion:
In this blog, we have introduced you to core web vitals and how you measure, audit, and optimize them. Implement these tips right away and improve the user experience. If you have any questions, please connect with our search marketing and web development experts.