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A website’s performance isn’t just a nice-to-have; it’s a make-or-break factor. Think of your website as a storefront. Imagine customers get frustrated if the door takes ages to open, the shelves are a jumbled mess, or they can’t seem to click on anything without the whole display shifting around them.

Core Web Vitals (CWV) scores tell you if you’re running a tight, welcoming website or one that’s on desperate need of an efficiency overhaul.

Better yet, getting these metrics right isn’t just about making users happy. It’s the key to unlocking higher online visibility and drawing in more organic traffic.

At Matchbox Design Group, we understand the critical importance of Core Web Vitals and our team employs a range of specialized services to ensure your website excels in performance, reliability, and responsiveness.

In this article, we’ll break down why Core Web Vitals matter and explore the best tactics to improve your site’s scores. 

What Are Core Web Vitals and Why Should You Care?

Core Web Vitals (CWV) represent a set of metrics that Google considers important for your website’s overall user experience. They play a huge role in understanding how users interact with your site, focusing on loading times, interactivity, and visual stability.

Why should you pay attention to these metrics?

Well, they directly impact your site’s SEO ranking and attract more visitors. A smooth, fast, and stable website enhances user experience, encouraging visitors to stay longer and engage more deeply with your content.

Additionally, it’s easier for Google’s crawlers to navigate and understand, resulting in faster and more accurate page indexing.

Lastly, optimizing your website’s Core Web Vitals not only improves user experience but also enhances data protection. A website that responds quickly and efficiently typically has a smaller attack surface, meaning there are fewer opportunities for attackers to exploit vulnerabilities.

This is because fast websites often employ streamlined code and efficient server configurations, which can reduce potential entry points for attackers.

Understanding The Three Core Web Vitals Metrics


Web vitals metrics are a set of measurements that assess the user experience of a web page. They are used by Google to evaluate the performance of websites and determine their ranking in search results. 

Largest Contentful Paint (LCP)

Largest Contentful Paint (LCP) measures the time it takes for the largest content element on your page to load. This could be an image, video, or a large block of text. The faster this content loads, the better the experience for your users.

Ideally, your LCP should occur within 2 seconds of when the page first starts loading. Achieving this score means your site is on the right track to providing a great user experience.

First Input Delay (FID)

First Input Delay (FID) focuses on interactivity. It measures the time from when a user first interacts with your page (like clicking a link or tapping on a button) to the time the browser is able to respond to that interaction. Quick responsiveness is key to a smooth user experience.

An ideal FID score is below 100 milliseconds. Achieving this indicates your website responds swiftly to user inputs, a critical aspect of user satisfaction.

Cumulative Layout Shift (CLS)

Cumulative Layout Shift (CLS) quantifies how often users experience unexpected layout shifts. These shifts can be frustrating and lead to a poor user experience. A low CLS score means your page is visually stable.

An ideal CLS score is less than 0.1. This demonstrates that your website offers a stable and predictable browsing experience, crucial for keeping your visitors happy and engaged.

Optimizing Your Website for Core Web Vitals

Optimizing your website for Core Web Vitals is not just about improving numbers; it’s about enhancing the overall user experience.

Reduce Render-Blocking JavaScript

Render-blocking JavaScript refers to scripts that must be processed before the browser can render the page. These scripts can delay the loading of important content.

When a browser encounters a <script> tag while parsing HTML, it generally stops rendering to fetch and execute the script. This can be problematic for scripts that aren’t immediately needed to display the initial content of a webpage. The delay caused by these render-blocking scripts negatively impacts the user experience, leading to a slower perceived load time.

Techniques to Reduce Render-Blocking JavaScript

  1. Script Placement: A simple approach is to move <script> tags that are not essential for initial rendering to the end of your HTML body just before the closing </body> tag. This way, the browser can parse and render the main content before processing these scripts.
  2. async and defer Attributes:
  • async: Scripts with the async attribute are fetched in parallel with HTML parsing and executed as soon as they are ready. This is ideal for scripts that don’t depend on other scripts or the DOM being fully loaded.
  • defer: Scripts with the defer attribute are fetched in parallel but executed only after the HTML parsing is complete, in the order they appear in the code. Use defer for scripts that might need to interact with the DOM or other scripts.
  1. Code Splitting: Code splitting involves breaking down your JavaScript code into smaller, manageable chunks (bundles) and loading them on demand when they are needed. This is a more advanced technique but can significantly improve performance, especially for larger applications.

Leverage Browser Caching

Browser caching stores copies of resources directly in the user’s browser, so they don’t need to be downloaded again on subsequent visits. This significantly speeds up loading times for returning visitors.

To implement effective browser caching, configure your server to use cache-control headers. They instruct the browser on how long to store the cached resources. Carefully set these parameters, and ensure that users have a fast experience while still receiving the most up-to-date content.

Cache-Control Header Parameters:

  • max-age: The primary way to control caching. It specifies how long (in seconds) a resource should remain valid in the browser cache. For example, max-age=3600 means the browser can keep the file cached for one hour.
  • no-cache: Forces the browser to validate the resource with the server before using it, even if there’s a cached version.
  • no-store: Instructs the browser not to store the resource in its cache at all.
  • public: Indicates the resource can be cached by any cache (browser, CDN, etc.).
  • private: Indicates the resource should only be cached by the user’s browser and not by shared caches (like CDNs).

Optimize And Compress Images

Images often account for the largest portion of bytes downloaded on a web page. Optimizing these images can lead to significant improvements.

Start by resizing images to the maximum display size they will appear on your site. The WebP image format created by Google, provides high-quality images at smaller file sizes. Tools like Squoosh or ImageOptim can help compress and optimize your images without sacrificing quality.

In your HTML code, specify the width and height of images using the width and height attributes. This prevents the browser from needing to recalculate the layout as images load, improving perceived performance.

This practice ensures that the rest of your content flows around these elements predictably, maintaining a stable and visually consistent layout.

Minimize JavaScript Execution Time

JavaScript execution can significantly affect your site’s responsiveness. To minimize JavaScript execution time, start by removing any unused code.

Next, consider minifying your JavaScript. Minification removes unnecessary characters from your code (like whitespace and comments) without changing its functionality. This reduces file sizes and speeds up loading times.

Specific Techniques to Optimize JavaScript Performance

  • Code Profiling: Use browser developer tools (like the Performance tab in Chrome) to identify bottlenecks in your JavaScript code. This helps pinpoint which functions or operations consume the most time, allowing you to focus your optimization efforts.
  • Efficient DOM Manipulation: The Document Object Model (DOM) represents the structure of your webpage. Excessive or inefficient DOM manipulation can be slow. 
  • Asynchronous Operations (Promises and Async/Await): Use Promises or the more modern async/await syntax to handle tasks that might take time (like network requests or user interactions). This prevents your JavaScript from blocking while waiting for these operations to complete, improving responsiveness.
  • Web Workers: For computationally intensive tasks, offload them to Web Workers. These run in separate threads, so they won’t block the main thread responsible for rendering your UI.
  • Lazy Loading: Load scripts only when they are needed. You can use the defer or async attributes in your <script> tags or dynamically load scripts using JavaScript.
  • Tree Shaking (with Modern Bundlers): Tools like Webpack and Rollup can automatically eliminate unused code during the build process, further reducing file sizes.

Reduce Third-Party Scripts

Third-party scripts, such as analytics or advertising tools, can slow down your site. Each script you add increases the potential for delays in processing user inputs.

To mitigate this, audit your third-party scripts regularly. Remove any that are not essential. For those that are necessary, look into combining scripts or hosting them locally. This reduces the number of requests your site makes.

Use Preloading or Prefetching for Critical Resources

Preloading and prefetching are techniques to load resources before they are needed. While preloading is for resources needed on the current page, prefetching loads resources for future pages.

Use <link rel=”preload”> for critical resources that affect the current page and <link rel=”prefetch”> for resources likely to be used in subsequent pages. This strategic loading minimizes layout shifts by ensuring resources are ready when needed.

Avoid Lazy Loading Above-the-Fold Content

Lazy loading defers the loading of resources until they are needed, which is great for improving initial page load times. However, applying lazy loading to above-the-fold content can cause layout shifts as the content pops into view.

Ensure that content critical to the initial view is loaded normally. Reserve lazy loading for images, videos, and other resources below the fold or in off-screen tabs.

Debounce or Throttle Animations

Animations can contribute to layout shifts if not handled properly. Debouncing and throttling are techniques to limit the frequency of function executions, which can be applied to animations to reduce their impact on CLS.

Debouncing ensures that a function (like an animation trigger) is executed only after a certain amount of time has passed without it being called again. Throttling limits the execution of a function to once every specified number of milliseconds. Applying these techniques to animations can help maintain a stable layout.

A stable site builds trust with your users, encouraging them to engage more deeply with your content.

Why Hosting Matters for Core Web Vitals

Photo by Panumas Nikhomkhai on Pexels

The quicker your server responds, the faster your content starts loading on the user’s screen. Additionally, reliable uptime guarantees that your site is always available, ensuring a consistent user experience.

Server Location

The physical location of your hosting servers can affect the speed at which your content is delivered to users. Closer server locations to your audience mean lower latency and faster loading times, directly benefiting your Core Web Vitals. Almost all hosting providers offer Content Delivery Network (CDN) services, distributing your content across a global network of servers to ensure fast delivery worldwide.


As your website grows, so does the need for resources. A hosting service that offers easy scalability can help you manage increased traffic without negatively impacting your Core Web Vitals. Being able to quickly upgrade your hosting plan or resources ensures that your site remains fast and responsive, even during traffic spikes.

Choosing the Right Hosting for Core Web Vitals

When selecting a web hosting provider, consider the following factors to ensure it supports your Core Web Vitals optimization efforts:

  • Performance: Look for hosting services known for their speed and reliability. Check independent reviews and performance benchmarks.
  • CDN Availability: A CDN can significantly improve your site’s loading times for users around the world. Some hosting providers include CDN services in their plans.
  • Scalability: Ensure the hosting service allows you to easily upgrade your plan or resources as your site grows.
  • Support for Modern Technologies: Hosting that supports the latest web technologies, such as HTTP/2 and PHP 7+, can improve your site’s efficiency and speed.
  • Security: A secure hosting environment protects your website application from cyber attacks that could affect availability and performance.

Investing in quality hosting is investing in your website’s future.

Tools and Resources for Monitoring Core Web Vitals

Monitoring your website’s performance is key to understanding and improving Core Web Vitals. Fortunately, there are several tools at your disposal to help track these metrics and identify areas for improvement.

Google Search Console Core Web Vitals Report

Google Search Console offers a Core Web Vitals report that provides an overview of how your pages perform based on real-world usage data.

This tool segments reports into mobile and desktop performances, helping you pinpoint where your site needs the most work.

PageSpeed Insights

PageSpeed Insights is a tool that analyzes the content of a web page, then generates suggestions to make that page faster.

It provides both lab and field data about a page, including Core Web Vitals scores. This makes it invaluable for both quick assessments and deeper analyses.


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. Lighthouse can be run in Chrome DevTools, from the command line, or as a Node module. You can use Lighthouse to audit your Core Web Vitals, getting detailed insights and recommendations for improvement.


WebPageTest allows you to test your website’s performance from different locations around the world, using real browsers at real consumer connection speeds. It provides detailed insights into your site’s load times, which can help you understand how geographical location affects your Core Web Vitals.


Optimizing Core Web Vitals is fundamental to providing a positive user experience on your website. They influence not only your SEO rankings but also how users perceive your site. By focusing on optimizing these vital metrics, you can ensure your site is fast, responsive, and stable.

Start by assessing your current performance with the tools mentioned above. Identify the areas where your site needs improvement and prioritize those changes. Remember, optimizing for Core Web Vitals is an ongoing process. Regular monitoring and adjustments are necessary to maintain a high-quality user experience.

Partnering with Matchbox Design Group means more than just a website; it’s a commitment to delivering a seamless online experience that drives results. Let us optimize your website for Core Web Vitals and elevate your digital presence today.

Contact Matchbox Design Group Today!

If your website could use a refresh or you’re looking to drive more traffic to your site, fill out the form below and we’ll contact you to learn more about your digital needs.

Author Bio

Radostin Anastasov

Radostin Anastasov is Content Specialist at SERanking. He has acquired his marketing and PR experience across various industries, such as AI, finance, and communications. When he’s not busy writing, he plays basketball to rock music.