In June 2021, Google rolled out a major algorithm that suggested Core Web Vitals as a major ranking factor. This means that the page experience became one of the crucial factors in ranking the SERPs.
What are the core web vital factors that affect page signals, and how to improve the page experience? In this blog, we will share everything you need to know about Core Web Vitals.
What is Core Web Vitals?
Core Web Vitals are speed metrics that are part of Google's Page Experience signals, used to assess user experience. The metrics assess visual load using Largest Contentful Paint (LCP), visual stability using Cumulative Layout Shift (CLS), and interactivity using First Input Delay (FID).
Core Web Vitals considers these metrics for improving page experience:
- Page loading performance
- Ease of interaction
- Visual stability of a page
These metrics offer a unique perspective on various elements that influence how users interact and engage with a website. While developers must consider "user experience" holistically, these independent metrics help break down these variables into bits and pieces so that site owners can identify and fix technical issues across their websites.
Why are Core Web Vitals Important?
Since core web vitals are just one of Google's page experience signals, they can't automatically alter a website's ranking on the SERPs. However, having high scores in these metrics can improve the overall user experience and help a website rank higher.
Some common ways to improve core web vital factors include:
- Increasing LCP loading speed by optimizing images and reducing server requests.
- Improving visual stability.
- Improving interactivity by minimizing first input delays.
It's important to note that a high page experience score will not automatically propel you to the top of Google. For example, if your website has a high LCP score but poor visual design and layout, it may still not be as user-friendly as sites with lower scores but superior design.
Core Web Vitals Metrics
The Google algorithm considers three major elements of core web vitals as a ranking factor. These are:
- Largest Contentful Paint (LCP)
- First Input Delay (FID)
- Cumulative Layout Shift (CLS)
However, there are some additional web vital factors as well. These are “Time to First Byte (TTFB) and First Contentful Paint (FCP).” “Total Blocking Time (TBT) and Time to Interactive (TTI) help measure interactivity.”
Largest Contentful Paint (LCP)
Largest Contentful Paint is the largest paint operation performed by a component within a web page. This metric measures how much work is required to render all of the content on a web page.
Larger pages will require more resources from the browser to load and render correctly.
Site owners want their pages to load quickly to provide a pleasant user experience. Quick load time is vital for a positive user experience; a page that loads quickly is more likely to rank higher on Google.
Furthermore, quick load times have been shown to affect engagement and conversion rates compared to a page with slow loading times.
1.1 What does LCP measure?
LCP measures the amount of time the page takes to load different content blocks in a single viewport. This metric only considers the speed with which content sections render on the visible screen; nothing below the fold is considered.
The optimum LCP for a page should be 2.5 seconds.
1.2 How to improve LCP?
The Page Speed insights give the right suggestions to optimize your page for LCP. Here are a few tips to improve LCP:
- Optimize your images: Make sure to deliver your images in lighter formats and compressed images. Enable compression on your web server by configuring GZIP acceleration.
- You can use an image compressor plugin that delivers the images in the right formats and compresses the images.
- Almost all websites are indexed by Google using mobile-first indexing. As a result, optimizing LCP for mobile is more important than optimizing it for desktop. Every image must be scaled down to fit the layout's specifications.
- Preload critical resources: Make sure that your servers preload critical resources like videos and fonts so that they are ready when the user requests them. This will reduce the loading time of your page by requiring less from the browser's cache.
- Reduce server response time: When a server takes a long time to respond to a request, the time it takes to render the page on the screen increases as well. As a result, it harms every page speed statistic, including LCP. The best practice is to use the Content Delivery Network (CDN) or optimize and analyze your servers.
- Remove render-blocking resources: The browser parses the DOM tree when it gets the HTML document from your server. If the DOM contains any external stylesheets or JS files, the browser must halt before continuing to parse the rest of the DOM tree. Render-blocking resources are JS and CSS files that cause the LCP time to be delayed.
Cumulative Layout Shift (CLS)
Cumulative Layout Shift is a metric that helps identify links or buttons that adjust after a web page has loaded and reflects the level of difficulty users will have engaging with elements on your site once a page renders. In other words, it checks if the elements move around the screen when a page is loading.
A strong user experience requires good UX and design, and a user will get frustrated if a web page switches elements while they are reading. CLS assists developers in determining whether pictures or links on a website shift, allowing site owners to improve accessibility, increase click-through rates, and increase online sales.
2.1 What does CLS measure?
CLS determines whether elements in the visible viewport change position between two rendered frames. In layman's terms, this metric assists site owners in determining whether content such as text, buttons, and banners are being pushed around while a user is reading content on a given page.
Elements that change position can confuse users and impede their experience on a page, so it's critical to ensure that all content remains in place after the page loads on the user's device.
Site owners should maintain a CLS of 0.1 or less.
2.2 How to improve CLS?
Here are the best practices to minimize the CLS:
- Use the set size dimensions for any media: Whenever you're using media, use the correct dimensions and settings. Setting incorrect dimensions can cause elements to shift around on a page, which will lead to an increased CLS score.
- Minimize Flash objects: Using too many Flash objects can also increase CLS because they often contain hidden code interacting with the DOM. By avoiding unnecessary Flash objects, you'll improve your overall site performance and reduce the chance of elements loading slowly.
- Add new UI elements before fold: Whenever you add new UI elements to a page, make sure they're added before any folds in the layout. This will ensure that the newly inserted element doesn't end up on top of an existing element, which can cause it to shift and incur a CLS penalty.
First Input Delay (FID)
FID is the time that elapses between when a user interacts with your page and when the page responds. It is also referred to as responsiveness.
FID measures the time it takes for a page to respond after a user has interacted with it. The goal is to reduce delays so that users have an enjoyable experience, whether they're browsing through content or interacting with questions or forms on your site.
3.1 What does FID measure?
When a page loads element inputs from a user, FID measures its responsiveness. FID only captures events like clicks and key presses in this mode.
FID should be kept below 100 milliseconds to ensure a decent user experience.
FID is difficult to quantify because this information can only be obtained in the field. This means that factors beyond your control, such as user device capacity and Internet speeds experienced by your audience, will affect your score.
3.2 How to improve FID?
There is no one solution to improving your FID score. However, by following a few simple guidelines, you can make a big impact:
- Remove non-critical third-party scripts: Remove any third-party scripts that are not essential for your site's functioning. This includes "social media plug-ins," ads, and Google analytics scripts. If a script is necessary but can be deferred, make sure to defer it as early as possible in the page loading process so users have a better experience. Minimize image and Flash downloads.
- Use a browser cache: This allows your page to load material more quickly. This speeds up the loading of JS tasks in your user's browser.
What are the Other Core Web Vitals Performance Metrics?
Core Web Vitals provides tons of data that developers can utilize to improve the user experience of their websites. Developers can also learn how their code affects how people consume content on their site and the main metrics described above.
These metrics describe lag times or other technical variables that might negatively affect how an online audience connects with a web page, so let's look at a few other metrics you can use to evaluate the experience visitors have on your site.
First Contentful Paint (FCP)
First Contentful Paint (FCP) is the amount of time it takes a user's browser to display DOM elements (images, non-white canvas components, and SVGs).
This metric is available in the range of FCP scores as given:
- 0–2 seconds: Green (fast)
- 2–4 seconds: Orange (moderate)
- 4+ seconds: Red (slow)
Time To Interactive (TTI)
Time to Interactive is the amount of time it takes the user's browser to execute a first simple request after starting your page. This includes anything from loading scripts, gathering data from the server, and rendering HTML.
The scores for Time To Interactive are as follows:
- 0–3.8 seconds: Green (fast)
- 3.9–7.3 seconds: Orange (moderate)
- 7.3+ seconds: Red (slow)
Total Blocking Time (TBT)
- 0–300 ms: Green (fast)
- 300–600 ms: Orange (moderate)
- 600+ ms: Red (slow)
Q. Do Core Web Vitals affect SEO?
Ans: Yes, Core Web Vitals are a ranking signal, according to Google. Google's web.dev provides excellent guidance on optimizing your LCP, FID, and CLS to improve your users' experience and rankings.
Q. Is Core Web Vitals just for mobile?
Ans: No, Core Web Vitals equally impact both desktop and mobile sites. But, you can get the page experience update for both desktop and mobile separately.
Q. When did Google introduce Core Web Vitals?
Ans: Google introduced Core Web Vitals in June 2021 as a way for site managers to measure the speed and performance of their websites.
Q. How do I check my Core Web Vitals for a website?
Ans: Chrome DevTools is a developer tool that comes pre-installed with the Chrome browser. Simply right-click and select "Inspect," and Chrome DevTools will launch. You may find some Core Web Vitals metrics using the Chome DevTools Performance panel. Simply keep an eye on Web Vitals.
Q. Does a cumulative layout shift affect your SEO?
Ans: The Cumulative Layout Shift is a crucial indicator for determining visual stability. It counts the number of times users are surprised by unexpected layout changes. As a result, a lower CLS score indicates that the content is stable and not altering, whereas a high CLS indicates that the content is shifting.
Some of the best practices that you can incorporate into your website to improve performance are: minifying code, using progressive enhancement, and optimizing images. By following these tips, your website will load faster for visitors and also help optimize your rankings on search engines.
You can use tools like GTMetrix or Lighthouse to check the page speed insights absolutely for free.