What are core web vitals?

We’ll walk you through 3 most important metrics you need to keep in mind when optimizing your websites performance, which are called Core Web Vitals (CWV) and they all together measure the quality of your visitors' user experience.

How do Core Web Vitals compare to the speed score?

Core Web Vitals and speed scores are related but represent different perspectives on website performance. 

Core Web Vitals: These are specific metrics (Largest Contentful Paint, First Input Delay, and Cumulative Layout Shift) that focus on the user experience. They directly measure how users perceive the speed, interactivity, and visual stability of a web page. 

Speed Score: This is a more general term related to a website’s speed and performance. While it may include some of the same metrics as Core Web Vitals, it also includes other factors, making it a broader evaluation.

In summary, Core Web Vitals are a subset of the broader category of metrics that contribute to a website’s overall speed and performance, as represented by a speed score. Both are valuable for assessing and improving a website, but Core Web Vitals have gained particular attention due to their direct connection to user experience and search engine rankings.

How are core web vitals measured?

Core Web Vitals are measured using specific performance metrics that focus on key aspects of the user experience. The three core metrics are:

Largest Contentful Paint (LCP):

• Definition: LCP measures the time it takes for the largest content element (such as an image or text block) to become visible within the user’s viewport.
• Ideal Performance: To provide a good user experience, LCP should occur within the first 2.5 seconds of the page starting to load.

First Input Delay (FID):

• Definition: FID quantifies the responsiveness of a webpage by measuring the time it takes for the page to respond to the first user interaction, such as a click or tap.
• Ideal Performance: FID should be less than 100 milliseconds to ensure a smooth and interactive user experience.

Cumulative Layout Shift (CLS):

• Definition: CLS evaluates the visual stability of a webpage by measuring the cumulative impact of unexpected layout shifts of visual elements during the entire loading process.
• Ideal Performance: A CLS score of less than 0.1 is considered good, indicating minimal visual disturbance for users.

Why do I need to pass Core Web Vitals?

Passing Core Web Vitals is crucial because it means your website is more user-friendly. It loads fast, reacts quickly to clicks, and stays stable visually, making visitors happy. Plus, search engines like Google use these measures to decide which websites to show first. So, if your site does well in Core Web Vitals, it not only gives a better experience to your visitors but also helps your website rank higher in search results. It’s like making your store both friendly to customers and easy to find in a crowded market.

Does passing Core Web Vitals affect my SEO?

Yes, passing Core Web Vitals can significantly impact your SEO (Search Engine Optimization). Search engines, including Google, use Core Web Vitals as a key factor in determining how well a website performs in terms of user experience. Websites that meet or exceed the recommended benchmarks for metrics like Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS) are considered more user-friendly. 

Here’s how passing Core Web Vitals can affect your SEO:

• Improved Rankings: Search engines aim to provide users with the best possible experience. Websites that offer a fast, responsive, and visually stable experience are more likely to rank higher in search results.
• User Experience Focus: Core Web Vitals are designed to measure aspects of your website that directly impact user experience. Search engines prioritize sites that prioritize user satisfaction, and passing these metrics demonstrates your commitment to providing a positive experience.
• Search Result Features: Google has integrated Core Web Vitals into its search algorithms, and websites that excel in these metrics may be more likely to appear in special search result features or carousels, further boosting visibility.
• Mobile Friendliness: With an increasing number of users accessing the internet via mobile devices, Core Web Vitals play a crucial role in determining how mobile-friendly your website is. Mobile-friendliness is a known factor in search rankings.

In summary, passing Core Web Vitals is not only about creating a better experience for your website visitors but also about aligning with search engine algorithms that prioritize user satisfaction. This alignment can positively influence your website’s ranking in search results, potentially leading to increased visibility and organic traffic.

Can I just pass Core Web Vitals on the homepage?

Focusing only on the homepage is a good starting point that ensures a positive first impression, but usually, your users navigate through multiple sites. To make a consistently excellent user experience it’s recommended to optimize Core Web Vitals across your entire site. 

It is more practical to focus on the homepage especially if other pages receive significantly fewer visits. However, if the website has more key pages it is crucial to extend optimization. Here are a few benefits:

• Consistent User Experience: Users might enter your website through different pages, not just the homepage. Optimizing Core Web Vitals across all pages ensures a consistent and positive experience, regardless of where users start their journey.
• Comprehensive Performance: Core Web Vitals consider various interactions, not just the initial load. Activities like clicking buttons, filling out forms, or viewing different sections also contribute to the overall user experience. Optimizing these interactions improves the comprehensive performance of your website.
• SEO Impact: Search engines evaluate Core Web Vitals across multiple pages to gauge the overall performance of your site. Consistent optimization enhances your chances of better rankings in search results, leading to increased visibility.

Where can I run a test for Core Web Vitals?

All of Google’s popular tools for web developers support the measurement of Core Web Vital. They provide an easy way to diagnose and fix user experience issues. This includes Lighthouse, PageSpeed Insights, Chrome DevTools, Search Console, web.dev’s measure tool, the Web Vitals Chrome extension and Chrome UX Report API.

Let’s go over the recommended basic workflow:

1. Use Search Console’s Core Web Vitals report to identify groups of pages that require attention.

1. Explore how visitors interact with your website by navigating to the Core Web Vitals section in the sidebar. Here, Google provides an overview of your URLs categorized as “Good,” “Needs Improvement,” or “Poor” in terms of user experience. The report is conveniently organized into mobile and desktop experiences, offering insights into performance on different devices.

2. To access a detailed breakdown of Core Web Vitals for your website, simply click on “Open Report.” The bar chart visually represents the number of pages that meet the Web Vitals thresholds and those that may require attention. By default, only pages categorized as “Poor” experiences are displayed, but you can expand your view by clicking on the “Need improvement” and “Good” headers to reveal comprehensive data across all categories.

3. Beneath the chart, you’ll find a section titled “Why URLs aren’t considered good,” which provides insights into the specific Core Web Vitals where your website may be falling short:

LCP issue: Indicates when the Largest Contentful Paint takes too long. 

CLS issue: Points out when Cumulative Layout Shift is higher than the desired level. 

FID issue: Signals that the First Input Delay is longer than optimal. 

Each issue is accompanied by information on the number of URLs affected in terms of rankings, offering a clear breakdown of areas that may need improvement for a more optimized user experience.

4. To see specific groups of pages that are impacted, click on each of the web vitals issues. At first, you will see just one URL. Click on the group to get the longer list of URLs in that group.URLs are in groups because Google doesn’t have enough data about every page so it groups them if pages are of similar type. This process isn’t perfect and sometimes some pages will be grouped even if they are not of similar type.

2. Once you’ve identified pages that need work, use PageSpeed Insights (PSI) to diagnose lab and field issues on a page. PSI is available via Search Console or you can enter a URL on PSI directly.