Core Web Vitals are performance metrics measuring loading speed, interactivity, and visual stability—which significantly impact your website’s usability and search rankings.
According to Google, websites that meet Core Web Vitals standards are 24% less likely to lose visitors due to slow performance. In this guide, we will break down Core Web Vitals, explore why they matter, and provide guides to improve core web vitals for WordPress.
Improving these metrics helps with rankings and boosts engagement and conversions. If you own a WordPress website, ranking higher on Google is likely one of your biggest goals. But did you know that Google now prioritizes user experience (UX) as a crucial ranking factor? This is why understanding Core Web Vitals is important and in this blog, you will also learn how to fix core web vitals issues as well.
Understanding Google Core Web Vitals & Their Impact on SEO
Website speed, responsiveness, and visual stability play a crucial role in user experience and search rankings. Google introduced Core Web Vitals as key performance indicators to measure these aspects, ensuring websites deliver a seamless browsing experience.
When a website fails to meet Core Web Vitals benchmarks, users experience slow loading times, delayed interactions, and unpredictable content shifts— all of which lead to frustration, increased bounce rates, and lower conversions. Since Google considers Core Web Vitals a direct ranking factor, optimizing them is essential for both SEO success and user satisfaction. Core Web Vitals consist of three key performance metrics:
🔹 Largest Contentful Paint (LCP) – Measures Loading Performance
LCP evaluates how quickly the largest visible content on a webpage loads. This could be a hero image, video, or large text block. A good LCP score is 2.5 seconds or faster. Anything above 4.0 seconds is considered poor. Slow LCP can result from unoptimized images, render-blocking resources, or slow server response times. To improve LCP, optimize images, use lazy loading, implement a CDN, and leverage caching.
🔹 First Input Delay (FID) / Interaction to Next Paint (INP) – Measures Interactivity
FID was replaced by Interaction to Next Paint (INP) in March 2024. INP measures the time delay between a user’s first interaction, such as clicking a button, and the browser’s response. This change provides a more comprehensive way to assess website responsiveness and user experience.
INP (Interaction to Next Paint) is a more comprehensive metric that measures the overall responsiveness of a page during the entire user session, not just the first interaction. A good FID is under 100ms, while an optimal INP score is below 200ms. Poor INP scores are often caused by heavy JavaScript execution and inefficient event handling. To improve INP, minimize JavaScript execution, reduce third-party scripts, and optimize main thread activity.
🔹 Cumulative Layout Shift (CLS) – Measures Visual Stability
CLS tracks how much content shifts unexpectedly while the page loads. A high CLS score means users experience sudden movements of images, buttons, or text, leading to accidental clicks and frustration. A good CLS score is 0.1 or lower. Common causes of CLS are missing width/height attributes for images, late-loading fonts, dynamically inserted ads, or iframes without reserved space. To improve CLS, define image dimensions, preload fonts, reserve space for ads, and use CSS aspect ratios.
Google has confirmed that Core Web Vitals directly affect search rankings. Websites with poor Core Web Vitals often see lower rankings and higher bounce rates. A case study from Web.dev showed that websites improving their Core Web Vitals saw an up to 15% increase in search visibility. Thus, optimizing these metrics is essential for both SEO and user experience.
How To Optimize Largest Contentful Paint (LCP) (Loading Speed)
LCP is one of the most crucial factors in Google Core Web Vitals. Your LCP should be 2.5 seconds or less. Users may abandon your site before engaging with your content if it takes longer to load.
1. Optimize Images and Videos
Unoptimized images are one of the leading causes of slow LCP. Use modern image formats like WebP instead of PNG or JPEG, as WebP images are 25-34% smaller while maintaining quality. Plugins like ShortPixel or Imagify can automatically compress images without noticeable quality loss. Additionally, lazy loading ensures images load only when needed, reducing initial load time.
2. Use a Caching Plugin
Caching can significantly speed up your site by storing a static version of your content. Plugins like WP Rocket or W3 Total Cache reduce the need for repeated server requests, leading to faster page loads.
3. Enable a Content Delivery Network (CDN)
A CDN stores copies of your website across multiple global locations. When users visit your site, the CDN delivers content from the nearest server, reducing load times. Popular CDNs like Cloudflare and BunnyCDN improve site speed dramatically.
4. Choose a Fast Hosting Provider
Your hosting provider plays a critical role in LCP performance. Avoid cheap shared hosting that slows down your site. Instead, opt for managed WordPress hosting services like xCloud, which optimize server performance for faster speeds.
Improving First Input Delay (FID) / Interaction to Next Paint (INP)
User interactivity is a crucial aspect of web performance, and First Input Delay (FID) is one of the key Core Web Vitals metrics that measure how quickly a webpage responds to user interactions. FID specifically tracks the delay between a user’s first interaction (like clicking a button or link) and the time the browser responds.
🚀 Google recommends an ideal FID of less than 100ms to ensure a smooth and responsive experience. However, Google will replace FID with Interaction to Next Paint (INP) in March 2024, making it even more important to optimize for responsiveness across an entire user session, not just the first interaction.
Why Is Optimizing FID/INP Important & How to Fix Core Web Vitals Issues?
A poor FID/INP leads to frustration, as users experience noticeable lag when clicking buttons or trying to interact with the page. Slow responsiveness negatively impacts user experience (UX), leading to higher bounce rates and lower conversions. Google considers FID/INP as a ranking factor, meaning better responsiveness can lead to higher SEO rankings.
To improve FID and INP, reducing main-thread blocking time and optimizing JavaScript execution are key. Below are some practical ways to enhance these metrics:
Minimize JavaScript Execution
One of the biggest contributors to poor FID/INP is excessive JavaScript execution. When a page loads, the browser must process all JavaScript before responding to user interactions. If there is too much JavaScript running at once, it blocks the main thread, preventing the page from responding instantly.
How to minimize JavaScript execution?
- Reduce Unnecessary JavaScript: Audit scripts and remove unused JavaScript files.
- Optimize WordPress Plugins: Many plugins load unnecessary scripts on every page. Tools like Perfmatters and Asset Cleanup allow you to disable scripts that aren’t needed for specific pages.
- Use Code Splitting: Instead of loading large JavaScript bundles all at once, split code into smaller, on-demand chunks.
- Optimize Third-Party Widgets: Some widgets (chatbots, pop-ups, and tracking scripts) slow down interaction. Only load them after user engagement.
Defer Non-Essential JavaScript
When JavaScript is loaded synchronously, it blocks other elements on the page from loading, which negatively impacts FID/INP. By deferring non-essential JavaScript, the browser can prioritize rendering critical content first while loading scripts in the background.
How to defer JavaScript?
- Use the Defer or Async Attribute: The defer attribute tells the browser to load JavaScript after the HTML has finished parsing.
- The async attribute loads scripts asynchronously, preventing them from blocking rendering.
- Use WordPress Optimization Plugins: If you are using WordPress, tools like WP Rocket offer built-in options to defer and delay JavaScript execution, improving interactivity.
- Lazy Load Third-Party Scripts: Delay non-essential third-party scripts (like chat widgets, analytics tracking, and social media embeds) until after user interaction.
Reduce Third-Party Scripts
Tracking codes, analytics tools, embedded videos, and advertising networks introduce additional JavaScript execution time, increasing FID/INP delays. Since these scripts come from external sources, they can not always be optimized directly, making it crucial to limit their impact.
How to reduce third-party script Impact?
- Audit & Remove Unnecessary Scripts: If your website loads multiple analytics tools, ads, or social sharing widgets, consider removing redundant ones.
- Use Tag Managers Efficiently: Google Tag Manager (GTM) allows conditional script loading, so tracking codes are only loaded when needed.
- Self-Host Critical Scripts: Hosting certain third-party scripts locally (like Google Fonts) can improve loading speeds.
- Load Ads Responsibly: Ads can cause layout shifts and interaction delays. Reserve ad space in advance and load it asynchronously to prevent blocking user interactions.
Enhancing Cumulative Layout Shift (CLS) (Visual Stability)
CLS measures how much a webpage’s content shifts unexpectedly. A good CLS score is 0.1 or lower. Poor CLS frustrates users, leading to bad UX and lower rankings.
1. Specify Image Dimensions
One of the most common causes of CLS is image loading without explicitly defined width and height attributes. When an image is inserted into a page without these attributes, the browser does not know how much space to allocate for it before the image fully loads. As a result, the page layout may shift as the image loads, pushing content up or down unexpectedly.
How to Fix This:
- Always define width and height attributes for all images in your HTML or CSS.
- If using WordPress, ensure that the theme and plugins you use automatically include proper dimensions when images are loaded.
- Use CSS aspect ratio boxes to reserve space for images before they load. This prevents content from shifting when the image appears.
- Utilize responsive images (srcset) to ensure images are appropriately sized for different screen resolutions, reducing unnecessary resizing.
2. Preload Fonts
Fonts are often an overlooked cause of CLS. When a website loads, it may use a fallback font until the custom web font is fully downloaded. This switch between fonts can cause a noticeable layout shift, especially if the custom font has different spacing or line heights.
How to Fix This:
- Use the font-display: swap; property in CSS to load a fallback font immediately while the custom font loads in the background. This prevents major shifts when the font finally loads.
- Preload key fonts using <link rel=”preload” as=”font”> in the <head> of your HTML to prioritize font loading early in the page lifecycle.
- Minimize the number of fonts used and host fonts locally rather than relying on third-party font providers like Google Fonts, which can introduce delays.
3. Avoid Dynamic Ads Without Space Reservation
Ads are one of the biggest contributors to layout shifts, especially if they load asynchronously or their dimensions aren’t predefined. When an ad loads and pushes existing content downward, it creates a poor user experience and increases CLS.
How to Fix This:
- Reserve space for ads by defining fixed dimensions in the HTML or CSS. This prevents the layout from shifting when the ad is loaded.
- Use CSS containers with a predefined height for ad placements to ensure stability.
- Implement lazy loading for ads so they load after the main content, but only if space has been reserved beforehand.
- If you use Google AdSense, enable the “Anchor Ads” setting, which ensures ads do not disrupt the page layout.
Choose the Right Hosting & CDN for Performance Boost
Your website’s hosting and CDN significantly impact Core Web Vitals. Slow servers lead to poor LCP, FID, and CLS scores. Choosing performance-focused hosting like xCloud, improves load times. Pairing hosting with a CDN like Cloudflare ensures faster content delivery worldwide.
xCloud provides optimized WordPress hosting with built-in caching, CDN, and performance tuning, ensuring faster Core Web Vitals scores.
Advanced Optimization Techniques for WordPress
For those looking to maximize performance and improve Core Web Vitals, implementing advanced optimization techniques can take your website speed and user experience to the next level. Below are some powerful strategies,
Implement Critical CSS for Faster Above-the-Fold Loading
Critical CSS ensures that the above-the-fold content (the visible part of a webpage before scrolling) loads instantly. This prevents layout shifts and improves Largest Contentful Paint (LCP) scores.
How to Implement:
- Use plugins like WP Rocket or Autoptimize to extract and inline critical CSS.
- Manually identify essential CSS and load it separately while deferring non-critical styles.
Upgrade to HTTP/3 for Faster Connections
HTTP/3 is the latest web protocol that reduces latency and enhances website speed by enabling faster, more secure connections through QUIC (Quick UDP Internet Connections).
Benefits of HTTP/3:
👉 Reduces connection times and enhances page loading speed.
👉 Improves website performance, especially on mobile devices.
👉 Offers better security with built-in encryption (TLS 1.3).
How to Implement:
- Many hosting providers like xCloud support HTTP/3 automatically.
- Use a content delivery network (CDN) like Cloudflare or BunnyCDN to enable HTTP/3.
Optimize Database Performance with WP-Optimize
Over time, post revisions, spam comments, and unnecessary data can slow down WordPress performance. Regular database optimization helps keep your site running efficiently.
How to Optimize:
- Use WP-Optimize or Advanced Database Cleaner to remove unnecessary data.
- Schedule automatic cleanups to delete transient data and post revisions.
Disable Unnecessary WordPress Features (Heartbeat API, Embeds, etc.)
WordPress runs background processes like the Heartbeat API, which can consume excessive server resources, affecting performance.
How to Disable:
- Use Perfmatters or Disable Heartbeat plugins to limit Heartbeat API frequency.
- Disable unnecessary features like embeds, emojis, and XML-RPC to reduce HTTP requests.
Implementing these advanced techniques helps you significantly improve your WordPress website’s speed, performance, and SEO rankings.
How to Track And Optimize Core Web Vitals Effectively?
Maintaining strong Core Web Vitals is essential for ensuring a fast, responsive, and user-friendly website. Optimization is not a one-time task. Regular monitoring with tools like Google PageSpeed Insights and Search Console’s Core Web Vitals Report helps track performance.
Conduct periodic website audits and stay updated with Google’s algorithm changes. Here is a detailed guide on how to track and optimize core web vitals effectively. To monitor your Core Web Vitals, you can use various tools that provide real-time and field data:
- Google PageSpeed Insights: Enter your website URL to get a detailed Core Web Vitals report along with recommendations for improvement.
- Google Search Console (Core Web Vitals Report): Offers insights into how real users experience your website across different devices.
- Chrome User Experience Report (CrUX): Collects anonymized field data from real users browsing Chrome to assess performance.
- Lighthouse: An open-source tool that provides lab data and actionable suggestions for improving web performance.
- Web Vitals Chrome Extension: A browser extension that allows you to measure Core Web Vitals in real-time while browsing your website.
Top Plugins to Improve Core Web Vitals for WordPress
To improve Core Web Vitals for WordPress and simplify optimization, you need to use dedicated WordPress plugins. Consider using these top plugins like,
- WP Rocket (Caching, minification, lazy loading)
- Autoptimize (CSS/JS optimization)
- Perfmatters (Reduce WordPress bloat)
- ShortPixel (Image compression)
- FlyingPress (All-in-one performance optimization)
Improve Core Web Vitals for WordPress and Enhance Your Website Performance
Improving Core Web Vitals is essential for better rankings and a seamless user experience. By optimizing LCP, FID/INP, and CLS, you can significantly enhance your website’s performance, reduce bounce rates, and improve engagement. Whether you’re using caching, a CDN, or optimizing JavaScript, each step contributes to a faster, more user-friendly WordPress site.
Start optimizing your Core Web Vitals today and watch your Google rankings improve! If you need help, test your site with Google PageSpeed Insights and follow the strategies mentioned in this guide.
Do you think this blog is helpful? Do not forget to subscribe to our blog to read more blogs. We would love to have you in our Facebook community where you can share your knowledge and views with others.
