Core Web Vitals – A Guide To Google’s New Ranking Signals 2021

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The fundamental aim of Google Search is to deliver high quality search results, making the world’s information universally accessible and useful in just one click.   

The first part of this is delivering good content: how well the information on your site answers users’ search queries. The second part of this involves user experience (UX), which Google calls search signals for page experience: how well users are able to navigate your site. Search signals currently include:

  • mobile friendliness
  • safe browsing
  • TTPS security
  • intrusive interstitial guidelines

Core Web Vitals represent the latest iteration of Google Search to improve the UX on sites. As the name suggests, Core Web Vitals will be at the core of search ranking. Until now, Accelerated Mobile Pages (AMP) has been the standard format used by sites to improve the quality of mobile UX: for instance, in ranking Google’s Top Stories. Now, AMP will be built into the framework of Core Web Vitals. 

If you have a website and want to give Search Engine Optimisation (SEO) a real go, you will need to understand Core Web Vitals and how they affect your site’s rankings on the Search Engine Results Page (SERP).

What are Core Web Vitals?

Core Web Vitals add three elements to Google Search’s ranking of page experience: 

  • loading time
  • interactivity
  • visual stability

Loading time 

lcp largest contentful paint

Measured by Largest Contentful Paint (LCP), it records how long it takes for a site’s main content to load. Generally speaking, the more content on your site, the longer the load time. Likewise, if you have high resolution images or video content, they will take some time to appear on users’ screens. An average of 5 seconds to load will cause your site to rank lower on the SERPs, leading to a lower amount of traffic. Slow server response times, render-blocking JavaScript, slow resource load times and client-side rendering all contribute to poor LCP. Google recommends sites aim for an LCP of 2.5 seconds, while 4 seconds or longer constitutes poor quality. 

Interactivity 

fid first input delay

Interactivity is measured by First Input Display (FID). FID measures the time elapsed between a user’s first interaction with a page and the start of the browser processing it. For instance, let’s say users are required to put their login details into a page. Pages with good FID scores mean that you can click into the username box and start typing in your details without much delay. First-party script execution, data-fetching, and third-party script execution are all common causes of poor FID quality. Google recommends sites aim for a FID score of 100 milliseconds or less, while 300 milliseconds or longer constitutes poor quality. 

Visual stability  

cls cumulative layout shift

Visual stability is measured by Cumulative Layout Shift (CLS). CLS measures the size and quantity of unexpected layout shifts which occur during the loading of a page. A layout shift is the movement of a visible element from one rendered frame to another. The best example of this is when users navigate to click a button on a webpage, before it shifts unexpectedly and another button is pressed. The most common causes of poor CLS quality are images with no dimensions, advertisements without dimensions, dynamically injected content, flashes of text, and documents which require modifications before loading. Google recommends sites aim for a CLS score of 0.1 or less, while 0.25 constitutes poor quality. 

How do I find Core Web Vitals data for my site?

The Core Web Vitals Report collects data for Core Web Vitals. You can see your site’s data quite simply by pasting your site’s URL into the Report and verifying it by adding an HTML file or code snippet to the <head> section of your homepage’s code. Here, you’ll be able to define the primary target country your site is reaching, and link your Google Analytics with your Search Console Account. 

After this, you will have access to a large amount of data, which is presented through tools such as Lighthouse, PageSpeed Insights. The Report shows how your site performs on the three metrics of loading time (LCP), interactivity (FID) and visual stability (CLS), by using real world usage data, or field data. Field tools are a form of Real Use Monitoring (RUM) which analyses real people in the world. It is contrasted with lab tools, which analyse potential users – say, before you launch your site or updates to it. 

Different data collection tools will be useful for different data you wish to see. For instance:

  • Search Console’s Core Web Vitals is beneficial for aggregate data about page performance;
  • Lighthouse and PageSpeed Insights diagnose lab and field issues for specific pages;
  • Lighthouse and Chrome DevTools give guidance on exactly what to fix about your pages.

As a rule of thumb, you will want your pages to meet Google’s high-quality thresholds (listed above) for 75% of visits. This will ensure that enough users are navigating to your site based on Google’s SERP algorithms. Anything lower than this is considered poor quality. 

The best way to understand these tools is to start using them. Access your Core Web Vitals Report, link your Google Analytics account to your Search Console Account, and start navigating. It will make far more sense once your website is displayed in context. 

Get a head start by investing in Core Web Vitals

Core Web Vitals are the latest edition of Google’s goal of delivering high quality search results. If you want to get the most out of your site’s ranking in SERPs, ensure that the three hallmarks of Core Web Vitals: loading time (LCP), interactivity (FID), and visual stability (CLS) are meeting Google’s thresholds for high-quality content. To view your site’s data, access Google’s Core Web Vitals Report, and analyse it using the suite of analytics tools on offer.  

The future of search is fast, consistent and delightful. Make sure you’re ahead of the curve: invest in Core Web Vitals!