- March 4, 2023
- Posted by: Campbell Scott
- Categories: Marketing, Technology
Core Web Vitals are a set of user-focused metrics introduced by Google to measure website performance and user experience. They are designed to help website owners identify and improve the most critical aspects of their website’s performance. Core Web Vitals consist of three metrics: Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS).
In this article, we will provide a comprehensive guide to Core Web Vitals, including why they matter for website owners, how to measure and improve them, and best practices for optimizing website performance. We will also provide examples of successful Core Web Vital optimizations to help you understand how to apply these metrics to your website. Whether you’re a website owner, developer, or marketer, understanding and optimizing Core Web Vitals can help improve your website’s performance, user experience, and search engine visibility.
Explanation of Core Web Vitals
Core Web Vitals are a set of metrics that measure specific aspects of website performance and user experience. They were introduced by Google as a way to help website owners and developers focus on the most critical aspects of website performance that impact user experience. The three Core Web Vitals metrics are:
Largest Contentful Paint (LCP) – measures the loading performance of a website, specifically the time it takes for the largest piece of content on the page to load.
First Input Delay (FID) – measures the interactivity of a website, specifically the time it takes for the website to respond to the first user input (such as a click or tap).
Cumulative Layout Shift (CLS) – measures the visual stability of a website, specifically the amount of unexpected layout shift that occurs during page load.
By measuring and optimizing these three Core Web Vitals metrics, website owners and developers can improve the overall user experience of their website, which can lead to higher engagement, better retention, and increased conversions. Additionally, optimizing Core Web Vitals can also improve a website’s search engine visibility, as Google has stated that these metrics are becoming increasingly important ranking factors for search results.
Importance of Core Web Vitals for website owners
Core Web Vitals are important for website owners because they directly impact user experience and engagement on their website. Research shows that users are more likely to abandon a website that takes too long to load or has poor interactivity and layout stability. By optimizing Core Web Vitals, website owners can improve the speed and responsiveness of their website, which can lead to better user engagement, increased time on site, and higher conversion rates.
In addition to improving user experience, optimizing Core Web Vitals can also improve a website’s search engine visibility. Google has stated that Core Web Vitals will be a ranking factor in their search algorithm starting in May 2021. This means that websites that perform well on these metrics will be more likely to rank higher in search results, which can lead to increased traffic and revenue.
Overall, Core Web Vitals are an important aspect of website performance and user experience that website owners should prioritize in order to provide a better user experience and improve their search engine visibility.
Overview of the three metrics: LCP, FID, and CLS
Largest Contentful Paint (LCP) – measures the loading performance of a website, specifically the time it takes for the largest piece of content on the page to load. This metric helps website owners and developers understand how quickly their website is loading and how long users are waiting for content to appear. The ideal LCP measurement is 2.5 seconds or faster.
First Input Delay (FID) – measures the interactivity of a website, specifically the time it takes for the website to respond to the first user input (such as a click or tap). This metric helps website owners and developers understand how quickly their website responds to user input and whether there are any delays that could impact user experience. The ideal FID measurement is less than 100 milliseconds.
Cumulative Layout Shift (CLS) – measures the visual stability of a website, specifically the amount of unexpected layout shift that occurs during page load. This metric helps website owners and developers understand whether the layout of their website is stable or if it shifts unexpectedly during loading, which can be frustrating for users. The ideal CLS measurement is less than 0.1.
By understanding these three Core Web Vitals metrics and how they impact user experience, website owners and developers can optimize their website’s performance to improve user engagement, retention, and conversions.
II. LCP (Largest Contentful Paint)
Largest Contentful Paint (LCP) is a Core Web Vital that measures the loading performance of a website. Specifically, LCP measures the time it takes for the largest piece of content on a web page to load, which is typically an image or video. This metric is important because it represents the point at which the user can actually see meaningful content on the page.
Why LCP Matters for User Experience and SEO
LCP is important for user experience because users expect websites to load quickly and be responsive. If a website takes too long to load, users are more likely to abandon the site or become frustrated, which can result in lower engagement and conversions. Additionally, LCP is also an important ranking factor for SEO, as Google has indicated that websites with a fast LCP will be given preference in search results.
Strategies for Improving LCP
There are several strategies website owners and developers can use to improve LCP, including:
Optimizing images – Images are often the largest piece of content on a web page, so optimizing them for faster loading can have a big impact on LCP. This can be done by reducing image file size, using the correct image format (such as JPEG for photos and PNG for graphics), and compressing images without sacrificing quality.
Minimizing render-blocking resources – Render-blocking resources are files that must be loaded before a web page can be displayed. By minimizing these resources, such as scripts and stylesheets, the page can load faster and improve LCP.
Using a content delivery network (CDN) – A CDN is a network of servers that can deliver content to users from a server that is geographically closer to them, reducing the time it takes to load content and improving LCP.
Best Practices for Optimizing Website Performance
In addition to optimizing LCP, there are several best practices for optimizing website performance that can improve user experience and SEO. These include:
Compressing images – Compressing images can reduce their file size without sacrificing quality, making them load faster and improving LCP.
Minifying code – Minifying code, such as HTML, CSS, and JavaScript, removes unnecessary characters and spaces, reducing file size and improving page load time.
Examples of Successful LCP Optimizations
One example of a successful LCP optimization is by The New York Times, which improved its LCP by compressing images and eliminating unnecessary code on its website. Another example is by e-commerce website Zulily, which improved its LCP by using a CDN to deliver content more quickly to their users.
By implementing these strategies and best practices, website owners and developers can improve their website’s LCP and provide a better user experience for their visitors while also improving their search engine visibility.
III. FID (First Input Delay)
First Input Delay (FID) is a Core Web Vital that measures the time it takes for a user’s first interaction with a website, such as clicking a button or filling out a form, to be responded to by the website. FID measures the delay between the user’s action and the website’s response, and is important for user experience because users expect websites to be responsive and react quickly to their actions.
Why FID Matters for User Experience and SEO
FID is important for user experience because it directly affects how users perceive a website’s responsiveness and interactivity. If a website is slow to respond to user input, users may become frustrated and disengage with the site, leading to lower engagement and conversions. Additionally, FID is also an important ranking factor for SEO, as Google has indicated that websites with a fast FID will be given preference in search results.
Strategies for Improving FID
There are several strategies website owners and developers can use to improve FID, including:
Reducing JavaScript execution time – JavaScript can be a major bottleneck for FID, so reducing the amount of time it takes for JavaScript to execute can improve FID. This can be done by optimizing code and reducing unnecessary computations.
Simplifying code – Complex code can also slow down FID, so simplifying code and reducing the number of dependencies can help improve FID.
Minimizing the impact of third-party scripts – Third-party scripts, such as those used for analytics or advertising, can also slow down FID. Minimizing their impact by reducing their usage or delaying their execution can improve FID.
Best Practices for Optimizing Website Performance
In addition to optimizing FID, there are several best practices for optimizing website performance that can improve user experience and SEO. These include:
Using lazy loading for images – Lazy loading delays the loading of images until they are needed, reducing the initial page load time and improving FID.
Deferring non-critical JavaScript – Deferring non-critical JavaScript, such as scripts for social media buttons, until after the page has loaded can improve FID.
Examples of Successful FID Optimizations
One example of a successful FID optimization is by website builder Wix, which improved their FID by optimizing their JavaScript and deferring non-critical code. Another example is by online retailer Wayfair, which improved its FID by simplifying its code and minimizing the impact of third-party scripts.
By implementing these strategies and best practices, website owners and developers can improve their website’s FID and provide a better user experience for their visitors while also improving their search engine visibility.
CLS (Cumulative Layout Shift)
Cumulative Layout Shift (CLS) is a Core Web Vital that measures the amount of unexpected layout shift that occurs during the loading of a web page. Layout shift occurs when elements on the page move or shift unexpectedly, and CLS measures the total amount of shift that occurs during the loading process.
Why CLS Matters for User Experience and SEO
CLS is important for user experience because unexpected layout shift can be disorienting and frustrating for users. When elements on a page suddenly move or shift during loading, it can cause users to lose their place and become confused about the content they were trying to interact with. Additionally, CLS is also a ranking factor for SEO, as Google has indicated that websites with a low CLS score will be given preference in search results.
Strategies for Improving CLS
There are several strategies website owners and developers can use to improve CLS, including:
Reserving space for images and ads – One common cause of layout shift is images and ads loading after the page has already started rendering. Reserving space for these elements can help prevent layout shifts.
Avoiding changes to layout during page load – Changes to layout during page load can also cause unexpected layout shifts. Avoiding these changes or using techniques like preloading can help improve CLS.
Best Practices for Optimizing Website Performance
In addition to optimizing CLS, there are several best practices for optimizing website performance that can improve user experience and SEO. These include:
Specifying image dimensions – Specifying the dimensions of images can help the browser reserve space for them and prevent layout shifts.
Avoiding large or complex animations – Large or complex animations can also cause layout shift, so it’s important to use animations judiciously and optimize them for performance.
Examples of Successful CLS Optimizations
One example of a successful CLS optimization is by the news website The Verge, which improved its CLS by reserving space for images and ads and optimizing its ad loading strategy. Another example is by website builder Squarespace, which improved its CLS by optimizing its image loading and using preloading techniques to avoid changes to layout during page load.
By implementing these strategies and best practices, website owners and developers can improve their website’s CLS and provide a better user experience for their visitors while also improving their search engine visibility.
V. Tools for measuring and improving Core Web Vitals
Measuring and improving Core Web Vitals is essential for website owners and developers who want to provide the best possible user experience and improve their search engine rankings. Fortunately, there are several tools available for measuring and improving Core Web Vitals.
Google’s Core Web Vitals Report in Search Console
Google’s Core Web Vitals Report in Search Console is a free tool that provides website owners and developers with an overview of their website’s Core Web Vitals performance. The report provides detailed information on each of the three Core Web Vitals metrics (LCP, FID, and CLS), as well as suggestions for improving performance. Website owners and developers can use this report to identify issues and track improvements over time.
Other Tools for Measuring Core Web Vitals
In addition to Google’s Core Web Vitals Report, there are several other tools available for measuring Core Web Vitals, including:
Lighthouse – Lighthouse is an open-source tool from Google that provides an automated audit of website performance, including Core Web Vitals. Lighthouse generates a report that includes detailed information on each metric and suggestions for improvement.
WebPageTest – WebPageTest is another free tool that provides website owners and developers with detailed information on website performance, including Core Web Vitals. WebPageTest allows users to test their websites from multiple locations and devices, providing a more comprehensive view of performance.
Strategies for Improving Core Web Vitals Based on Data from These Tools
Once website owners and developers have measured their website’s Core Web Vitals using these tools, they can use the data to identify areas for improvement. Some strategies for improving Core Web Vitals based on data from these tools include:
- Optimizing images and videos – Optimizing images and videos can help improve LCP and reduce the impact of these elements on CLS.
- Reducing JavaScript execution time – Reducing the amount of JavaScript on a page and optimizing its execution can help improve FID.
- Minimizing the impact of third-party scripts – Minimizing the impact of third-party scripts, such as ads and tracking codes, can help reduce the impact of these elements on FID and CLS.
- Using lazy loading for images – Lazy loading images can help improve LCP by reducing the amount of content that needs to be loaded initially.
By using these tools and implementing these strategies, website owners and developers can improve their website’s Core Web Vitals and provide a better user experience for their visitors.
Core Web Vitals are essential metrics that measure the user experience of websites. Poor performance on these metrics can lead to negative impacts on search engine rankings and user engagement. However, website owners can improve their website’s performance on Core Web Vitals by implementing various optimization strategies, such as optimizing images, reducing JavaScript execution time, and avoiding layout shifts during page load.
To measure and monitor Core Web Vitals, website owners can use tools such as Google’s Core Web Vitals report in Search Console, Lighthouse, and WebPageTest. These tools provide insights into specific issues that impact Core Web Vitals, allowing website owners to make data-driven improvements to their websites.
By following best practices and using the right tools, website owners can improve their website’s Core Web Vitals and provide a better user experience for their visitors. Ultimately, this can lead to better search engine rankings, increased engagement, and improved business outcomes.