Building your website must come with a purpose. It doesn’t end in professional design and functionalities. Nowadays, users often have a short attention span and expect attractive and fast-loading pages when they are browsing the web. Page speed and user experience are becoming more important than ever to capture your web visitors’ attention and hook them to your web pages.
As part of its efforts to create better web experiences for users, Google has developed Core Web Vitals – a set of metrics designed to measure the performance of any given page. By understanding these metrics, and taking necessary steps to improve score, businesses can ensure that their website is providing a great user experience every time.
What are Core Web Vitals?
Google plans to make page experience an official Google ranking factor. So, Google introduced core web vitals in May 2020 to provide a standardized set of metrics that apply to all web pages and should be measured by all site owners. The recent Google ranking algorithm demands more from web developers and content creators.
The core web vitals represents the set of factors that Google considers important for user experience. The website’s content loading speed, responsiveness, and visual stability are essential in measuring core web vitals. These metrics help to keep your web pages healthy. As a result, your site will have increased users’ recognition for being clean and hassle-free.
The goal of the core web vital is not to trick the search engine but to add high-quality content that enhances user experience (UX) on your web pages.
Why Is It Important?
Core Web Vitals are critically important for every website owner and user.
For site owners, these metrics provide tangible data regarding user experience, effectively measuring aspects like load time, interactivity, and stability of content while loading. A superior performance in these areas leads to enhanced user engagement, retention, and conversions.
For users, Core Web Vitals ensures a seamless, efficient, and enjoyable browsing experience, minimising frustrations brought about by slow load times, unexpected layout shifts, or lack of responsiveness to user input. To everyone, a smoother and more user-friendly internet experience makes the core web vitals important.
Three Main Performance Metrics of Core Web Vitals
To understand better, below are details of the three Core Web Vitals. These core metrics give you unified guidance to improve your web page performance and increase the quality of user experience (UX).
Largest Contentful Paint (LCP)
Largest Contentful Paint (LCP) measures the load time of the largest content element visible within the viewport. This could be a block of text, an image, or even a video. The largest contentful paint is all about how long it takes for the main content of a page to load – the quicker, the better.
Users can’t interact with a page before the main content has loaded, so the faster this happens, the quicker a user can start engaging with the page. A good LCP score helps ensure that your users’ attention is captured from the moment they land on your page, reducing bounce rates and improving overall user experience. Google suggests that an ideal LCP measurement should be within 2.5 seconds of when the page first starts loading.
Most Common Reason for Poor LCP:
The most common reasons for poor Largest Contentful Paint (LCP) scores include:
- Slow server response time: When a website’s server is slow to respond to a browser request, the largest content elements can take more time to render.
- Render-blocking JavaScript and CSS: Certain page elements can block the process of displaying an HTML page, causing a delay in loading website content.
- Slow resource load times: High-definition images and videos take more time to load compared to text, and placing them above the fold can negatively affect LCP.
- Client-side rendering: Client-side rendering can delay the display of content, affecting the LCP score.
- Lazy loading: While lazy loading can improve overall loading time, it can make the LCP score worse, especially when the LCP element is an image and gets lazy-loaded
How to Improve LCP:
- Remove unused third-party scripts because they slow down the loading speed by 34 ms each.
- Minify Cascading Style Sheets (CSS), HTML, or JavaScript files without affecting their operation. It may include line breaks, spaces, indents, and comments. Strip off unnecessary codes or data from the browser.
- Find a fast web hosting service provider to boost the loading speed of your web pages. The ideal measurement is less than 200 ms server response time.
- Use a lazy loading technique for images. They appear only when a user scrolls down the page of your site.
First Input Delay (FID)
First Input Delay measures the time it takes for a web page to respond to the first user interaction, such as clicking on a link or button. FID is essential because it reflects how responsive your website is to user input – the lower, the better.
For example, if a visitor clicks on a call-to-action button on your website and there is a delay in the website reacting to that input, it can lead to frustration and possibly result in the user leaving your site. Google suggests that an ideal FID measurement should be less than 100 milliseconds.
Most Common Reason for Poor FID:
The most common reasons for poor First Input Delay (FID) are:
- Heavy JavaScript execution: Heavy JavaScript bundles, both in initial payload and ongoing execution, can cause long first input delays. Browsers may take a long time to parse and evaluate these bundles, leading to slow response times.
- Blocked main thread: A blocked main thread can cause input delay. Web workers can help run JavaScript on a background thread, reducing main thread blocking time and improving FID.
- Inefficient JavaScript and CSS usage: Poor FID scores often indicate the need for improvements in JavaScript or CSS usage, as they often don’t run on the browser’s main thread and have different constraints.
- JavaScript size bloat: Excessive JavaScript size and heavy execution times can slow down how soon a page can respond to user input, leading to poor FID scores.
How to Improve FID:
- Optimize JavaScript parsing, compiling, and execution on your web page.
- Use web workers to run JavaScript on a background thread.
- Optimize images and code for efficient loading and execution.
- Serve content in a progressive manner to spread the workload and improve interaction readiness.
If you want to test the FID, open your Google Chrome, head over to “Lighthouse”, right-click it and click “Inspect”.
As a heads-up, the new core web vitals metric is underway. It is deemed to replace the First Input Delay metric. Instead of focusing on the user’s single interactions, it will scale up to monitoring groups of individual interactions as a part of the user’s input. It shall be like Input Response Delay versus Full Event Duration.
Cumulative Layout Shift (CLS)
Cumulative Layout Shift (CLS) is a core web vital that measures the visual stability of a web page. It is caused by elements that move around on a page’s layout while it is still loading, causing frustration for users. CLS score indicates how often these unexpected layout shifts occur and their severity – the lower, the better.
Google suggests that the ideal visual stability of a web page should be less than 0.1 seconds to provide a good user experience.
Most Common Reason for Poor CLS:
Some common reasons for poor cumulative layout shift include:
- Not setting dimensions for images, iframes, videos, or other embeds: Failing to specify the width and height attributes for image and video elements can cause unexpected layout shifts.
- Issues with custom font loading: Custom fonts that change the rendering behavior can cause text to be invisible or change size as they load in.
- Serving responsive ads with different sizes: Advertisements that change size or are served with different dimensions can cause layout shifts.
- Dynamically injecting content with plugins: Plugins that inject content dynamically, such as cookie consent notices or lead generation forms, can cause layout shifts.
- Using animations without the CSS Transform property: Animations without proper CSS transitions can lead to unexpected layout shifts.
- Poor internet connection: A slow internet connection can cause slow loading times, leading to poor CLS.
- Code issues: Numerous code issues, such as incorrectly implemented JavaScript or CSS, can result in poor CLS.
How to Improve CLS:
- Set Dimensions for Media Elements: Ensure that images, videos, and other media elements have specified dimensions to prevent unexpected shifts.
- Reserve Space for Ads and Embeds: Allocate space for ads, embeds, and iframes to prevent layout shifts when they load.
- Optimize Web Fonts: Address flashes of unstyled text by optimizing web font loading to minimize layout shifts.
- Avoid Dynamically Injected Content: Refrain from dynamically injecting content, such as ads and iframes, without specified dimensions to prevent layout shifts.
- Monitor and Debug: Use tools to monitor CLS, identify elements causing shifts, and debug issues to improve the overall user experience.
Other Performance Metrics
Speed Index
Speed Index measures how quickly the contents of a page are visibly populated. A lower speed index is better, and a score of 4,000 or less is considered good.
Time to Interactive (TTI)
Time to Interactive measures how long it takes a page to become fully interactive. It should be less than 3.8 seconds to provide a good user experience.
Total Blocking Time (TBT)
Total Blocking Time measures the total amount of time between First Contentful Paint (FCP) and Time to Interactive (TTI) where the main thread was blocked for long enough to prevent input responsiveness. It should be less than 300 milliseconds to provide a good user experience.
Tools
Now that you have understood the importance and functionalities of your site’s core web vitals. The next step is to streamline them using these tools to assess and measure the score of your site’s core web vitals.
PageSpeed Insights (PSI)
It measures the performance of a page both on mobile and desktop devices. The fast-performing page should fall within the range of 90%-100%.
The ideal threshold is more than 75% percentile of page loads across mobile and desktop devices.
PSI is a free tool with features that are quite easy to use. You just input the URL to begin the analysis and generate the report. The two data it provides are field and lab data. Between these two, field data give more relevant insight than lab data. The actual web user’s interaction with your site is the real-time collected data, whereas lab data is through simulation.
Google Search Console
Google Search Console operates in various levels of web analytics, such as monitoring, maintaining, and troubleshooting your website performance and present issues.
A few of its roles are to diagnose potential search engine optimisation (SEO) issues, make you understand your website’s popular pages, and facilitate organic traffic for a better ranking position. Its main difference from Google Analytics is it checks things before the users reach your website.
Chrome DevTools
It is a set of web developer tools that debug and allow you to edit a website as well as measure its performance. They are easy to access because they are built right into the browser. A few of its featured tools are as follows:
Lighthouse
It has been around but not quite known to many web developers, experienced ones and neophytes alike. As implied by its term, it sheds light on how to optimise your site. Lighthouse checks on web apps and generates feedback. It lets you know if your site practices are below the standards and provides tips on how to achieve better performance.
Web Vitals Chrome Extension
It assesses and renders feedback automatically. Three core features are working once this extension is installed: an ambient badge, detailed drill-down in the popup, and HUD overlay.
Ambient Badge shows if your site has passed the Core Web Vitals threshold scores. It comes with status signals.
- Disabled – grey
- Passing – green
- One or more metrics failing – red.
A detailed drill-down in the popup tells whether a user action is needed or a metric value might change.
The heads-up display (HUD) overlay paves the way for a persistent view of Core Web Vitals metrics during development.
Conclusion
Having an online presence is a crucial strategy. You must optimise the content and always be updated with the dynamics of Google ranking factors. Core web vitals’ heavy emphasis on the user’s quality page experience is advantageous to the success of your business. They help you to achieve higher engagement and conversion rates besides high visibility on Google search.
