Optimizing Core Web Vitals: A Step-by-Step Guideby@loado
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Optimizing Core Web Vitals: A Step-by-Step Guide

by LoadoJune 14th, 2023
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Core Web Vitals are a set of metrics that measure the performance and user experience of a website or app. Adopting these metrics can help you to improve the performance of your website and provide a better user experience for your visitors.
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In today's tech-savvy world, website performance is more crucial than ever. A site that loads swiftly and seamlessly not only provides a better user experience but also scores higher in search engine rankings, notably on Google. But how can you elevate your site's performance to meet these demands?

The answer lies in mastering and optimizing your Core Web Vitals - a set of metrics Google uses to evaluate site performance. But don't fret, if this concept seems alien to you. In this guide, we'll dive deep into the realms of Core Web Vitals, dissecting what they are, why they matter, and how you can optimize them to power up your site's performance.

Content Overview

  • Understanding Core Web Vitals
  • Why are Core Web Vitals Important?
  • The Three Pillars of Core Web Vitals
  • Tools for Measuring Core Web Vitals
  • Step-by-Step Guide to Optimizing Core Web Vitals
  • Leveraging Loado: Your Ally in Optimizing Core Web Vitals
  • Conclusion

Understanding Core Web Vitals

Core Web Vitals are a set of metrics that Google uses to measure the speed, responsiveness, and visual stability of a webpage. Introduced in 2020, they are part of Google's Page Experience signals, which contribute to a website's ranking in the search engine.

Web Vitals is an initiative by Google to provide unified guidance for quality signals that, according to them, are essential to delivering a great user experience on the web. "Core Web Vitals," a subset of Web Vitals, applies to all web pages, should be measured by all site owners, and will be surfaced across all Google tools.

The Core Web Vitals evolve annually, with Google adding or modifying metrics based on what they determine as crucial to a good user experience. Core Web Vitals include Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS).

Why are Core Web Vitals Important?

To simply put, Core Web Vitals are significant because Google says they are. That's enough to get any website owner or developer to sit up and take notice. But let's dig a little deeper.

With the proliferation of the internet, users' expectations have evolved dramatically. They demand fast, interactive, and stable experiences. Any deviation from this leads to a reduction in user satisfaction, which may manifest as decreased engagement, increased bounce rates, and negatively impact your overall conversion goals.

Google introduced Core Web Vitals to provide a quantifiable measure of user experience. These vitals are the foundation of a new page experience signal that combines existing UX-related signals (mobile-friendliness, safe browsing, HTTPS security, and intrusive interstitial guidelines). By using these signals, Google aims to help website owners, developers, and SEO professionals measure, benchmark, and improve their site’s user experience.

Moreover, these metrics directly influence a website's ranking on the Google search engine. Better-performing sites, with good Core Web Vitals scores, are favored by Google's algorithm, thereby appearing higher in search results.

The Three Pillars of Core Web Vitals

Now that we understand what Core Web Vitals are and why they matter let's delve into the three main pillars of Core Web Vitals.

Largest Contentful Paint (LCP)

LCP measures the time it takes for the main content on a webpage to load - from the moment a user clicks a link to the time the page's primary content has fully rendered on the screen. A good LCP score is anything under 2.5 seconds. Anything over 4.0 seconds is considered poor.

First Input Delay (FID)

FID quantifies a website's interactivity. Specifically, it measures the time from when a user first interacts with a webpage (like clicking a link or tapping a button) to when the browser processes that interaction. A good FID is less than 100 milliseconds, while anything over 300 milliseconds needs improvement.

Cumulative Layout Shift (CLS)

CLS gauges visual stability. It quantifies how much unexpected layout shift of visual content occurs on a webpage. This can be when a visible element changes its position from one rendered frame to the next. A low CLS, less than 0.1, is ideal, while anything above 0.25 is considered poor.

These three pillars, when taken together, offer a well-rounded picture of a webpage's performance. But how do you measure your Core Web Vitals?

Tools for Measuring Core Web Vitals

With the importance of Core Web Vitals well established, let's look at the various tools you can leverage to measure these critical metrics. Luckily, Google provides several tools to test and monitor your Core Web Vitals.

Here are a few you should familiarize yourself with:

  1. Google Search Console (GSC): The GSC has a dedicated Core Web Vitals report that groups pages by status, metric type, and URL group (group of similar web pages). It gives you a broad view of how your site performs and helps identify areas for improvement.

  2. PageSpeed Insights (PSI): PSI is a simple tool that reports on the performance of a page on both mobile and desktop devices and provides suggestions on how that page may be improved.

  3. Lighthouse: Lighthouse is an open-source, automated tool for improving the quality of web pages. It has audits for performance, accessibility, progressive web apps, SEO, and more. You can run it against any web page, public, or requiring authentication.

  4. Chrome User Experience Report (CrUX): CrUX is a public dataset of real user experience data on millions of websites. It measures field versions of all the Core Web Vitals.

  5. Chrome DevTools: DevTools are built directly into the Google Chrome browser and provide access to a wealth of data and services including measuring Core Web Vitals.

  6. Web Vitals Extension: This Chrome extension measures the three Core Web Vitals metrics in real-time on any webpage, allowing you to experience the page load like your users would.

With the knowledge of what tools are available for measuring Core Web Vitals, let's dive into the meaty part: the step-by-step guide to optimizing these vitals.

Step-by-Step Guide to Optimizing Core Web Vitals

Optimizing LCP

Improving your LCP score revolves around improving your page load time. Here are some strategies to achieve this:

  1. Remove any unnecessary third-party scripts: These additional scripts can significantly slow down your page load time, increasing your LCP.
  2. Upgrade your web host: Better hosting can improve server response time and, in turn, speed up the load time on your site.
  3. Set up lazy loading: Lazy loading ensures that images only load when someone scrolls to them, not all at once when the page loads.
  4. Remove large page elements: PageSpeed Insights will tell you if your page has an element that's slowing down the load time.

Optimizing FID

To optimize FID, you need to ensure that the browser can quickly respond to user interaction. Here are some steps you can take:

  1. Minimize (or defer) JavaScript: It's not about removing JavaScript, but optimizing its usage. The less a page has to load and execute, the less likely it interferes with user interactions.
  2. Remove non-critical third-party scripts: As with LCP, third-party scripts (especially those that load on the main thread) can negatively impact FID.
  3. Use a web worker: Web workers are a simple way to run JavaScript in the background without blocking the main thread.

Optimizing CLS

To enhance CLS, you need to minimize unexpected shifts in the layout of your webpage. Here are some strategies to consider:

  1. Use set size attribute dimensions for any media (video, images, GIFs, infographics etc.): This tells the browser exactly how much space a media item will take up, reducing layout shifts.

  2. Ensure ad elements have a reserved space: If you're inserting ads or embeds on your page, make sure to pre-allocate the right amount of space for it.

  3. Add new UI elements below the fold: This way, even if elements take longer to load, they won't push content down that the user may be reading or interacting with.

By following these guidelines and continually measuring, you can significantly optimize your website's Core Web Vitals. However, there's an even better way to streamline this process – using Loado, your ally in optimizing Core Web Vitals. Let's delve into how Loado can assist you.

Leveraging Loado: Your Ally in Optimizing Core Web Vitals

Loado is a real-user monitoring tool for websites that takes the guesswork out of Core Web Vitals optimization. It collects Core Web Vitals metrics directly from the users' browsers and provides insights using intuitive dashboards.

Here's how you can harness the power of Loado to optimize your Core Web Vitals:

  1. Monitor Performance in Real-Time: Loado provides real-time data about your website's performance, offering up-to-the-minute insights into how your site is functioning for actual users. This granular data allows you to identify and address performance issues as they happen.

  2. Measure Real User Experience: Unlike lab data that simulates user interactions, Loado captures real-world user interactions and their experience. This actual data helps you understand how your website performs in real-world conditions, leading to more accurate performance optimizations.

  3. Identify Bottlenecks: Loado allows you to spot bottlenecks in your website's performance swiftly. You can analyze how each page of your site is performing in terms of LCP, FID, and CLS and pinpoint exactly where improvements are needed.

  4. Compare and Track Changes: With Loado, you can track how your Core Web Vitals metrics change over time and measure the impact of the optimization strategies you implement.

  5. Easy-To-Understand Reports: Loado turns complex performance data into easy-to-understand reports. These insights empower developers, product managers, and marketers to make informed decisions about where to focus their efforts for the most significant impact on performance and SEO.

Using Loado alongside the step-by-step optimization guide we discussed can expedite your website's optimization process, improve your users' experience, and enhance your site's visibility on search engines.


Optimizing your website's Core Web Vitals is no longer a luxury - it's a necessity in today's highly competitive digital space. Not only do these optimizations elevate your users' experience, but they also signal to Google and other search engines that your site is high-quality, potentially boosting your rankings.

By understanding what Core Web Vitals are, why they matter, how to measure and optimize them, and leveraging tools like Loado, you're well on your way to transforming your website's performance.

Remember, optimization is not a one-and-done deal but a continuous process. Consistently monitor your metrics, tweak your strategies, and keep your website performance at its peak. The digital world is yours to conquer!


  1. Google Developers. "Core Web Vitals". Available at:
  2. Google Developers. "Web Vitals". Available at:
  3. Google Developers. "Largest Contentful Paint (LCP)". Available at:
  4. Google Developers. "First Input Delay (FID)". Available at:
  5. Google Developers. "Cumulative Layout Shift (CLS)". Available at:
  6. "How to Improve Largest Contentful Paint for Better Front-End Performance". Available at:
  7. Delaney, R. "How to Optimize Cumulative Layout Shift on WordPress (CLS)". Available at: