Core Web Vitals
Improve Ranking and Visitors Experience
Google Core Web Vitals for Wordpress: A Comprehensive Optimization Guide
The introduction of Google Core Web Vitals has significantly reshaped how websites are optimized for both performance and search rankings. With a primary focus on user experience, these metrics now play a pivotal role in determining how well a site ranks in search engines and how efficiently it delivers content to users.
This guide will explore how to optimize Core Web Vitals for WordPress, examining four critical categories: Performance, Accessibility, Best Practices, and SEO.
We’ll also break down the technical challenges and the tasks involved, with a focus on distinguishing between non-code and code-based optimizations.
01.Introduction to Core Web Vitals: Performance, Accessibility, Best Practices, and SEO
A positive Core Web Vitals Performance score directly influences your search engine rankings by improving page speed and user interaction. Sites that load faster, respond quickly, and maintain a stable layout keep users engaged longer and reduce bounce rates. Conversely, poor Core Web Vitals for WordPress Websites lead to higher abandonment rates, frustrated users, and lower rankings on Google.
Core Web Vitals measure key aspects of user experience and are categorized into three primary metrics:
- Largest Contentful Paint (LCP): The time it takes for the largest visible content to load, ideally within 2.5 seconds.
- First Input Delay (FID): Measures the time it takes for a page to become interactive, with a target of less than 100 milliseconds.
- Cumulative Layout Shift (CLS): Quantifies unexpected shifts in layout during loading, aiming for a score under 0.1.
Beyond these metrics, Accessibility, Best Practices, and SEO (non content related, also called technical SEO) also impact your site’s performance, engagement, and visibility. All of these factors play into how well your site ranks on Google and how users perceive and interact with it.
02. Performance Optimization:
Breaking Down Key Metrics
When it comes to performance optimization, Core Web Vitals for WordPress websites focus on load times, interactivity, and visual stability. Each metric represents a different aspect of a website’s speed and responsiveness.
1. Largest Contentful Paint (LCP)
LCP measures how long it takes for the most significant visible element on your site (like an image or block of text) to load. For a good LCP score, aim for less than 2.5 seconds. Here are some tasks involved in optimizing LCP:
- Non-code Optimizations: Compress images and serve them in modern formats like WebP. Utilize lazy loading to delay the loading of offscreen elements. Implement browser caching for faster resource delivery.
- Code-Based Optimizations: Reduce render-blocking resources such as JavaScript and CSS by deferring or minifying them. Optimize critical rendering paths by eliminating unnecessary code, which can help the browser focus on loading the most important content first.
2. First Input Delay (FID)
FID measures the time it takes for the browser to respond to a user’s first interaction, such as a click or a tap. A good FID score is under 100 milliseconds.
- Non-code Optimizations: Reduce the size of JavaScript files and defer non-critical JavaScript execution. Improve responsiveness by using asynchronous tasks.
- Code-Based Optimizations: Optimize JavaScript execution by breaking up long tasks and minimizing event listener complexity. Audit and replace heavy plugins that slow down interactivity.
3. Cumulative Layout Shift (CLS)
CLS is the measurement of unexpected visual shifts that occur as a page loads. A good CLS score is under 0.1. Reducing CLS involves stabilizing the layout to ensure that elements don’t shift unexpectedly while loading.
- Non-code Optimizations: Use defined dimensions for images, videos, and ads so that the space is reserved before the content loads.
- Code-Based Optimizations: Audit the layout of the page to ensure that UI components are coded with stabilized dimensions. Avoid dynamic elements that load late and push content around unexpectedly.
4. Avoid an excessive DOM size
To address the issue of “Avoid an excessive DOM size” and optimize page loading, it’s crucial to reduce the complexity and size of the DOM. Here are some practical strategies to achieve this:
Code-Based Optimizations:
- Remove unnecessary tags: Review your HTML code and eliminate any unnecessary tags or
divelements, especially those automatically generated by page builders like Elementor or Divi. - Minimize the use of deeply nested containers: Avoid overusing deeply nested elements like
div,span, or other tags. Simplify complex sections where multiple containers are stacked inside each other.
Impact of Large DOM Size on PageSpeed Insights
Having an excessively large DOM can significantly affect your PageSpeed Insights score, particularly in metrics related to interactivity and page responsiveness, such as:
- First Input Delay (FID)
- Time to Interactive (TTI)
- Total Blocking Time (TBT)
However, it’s challenging to determine exactly how many points are deducted directly due to a large DOM, as PageSpeed Insights calculates the score based on a combination of several factors (loading speed, interactivity, visual stability). The impact of a large DOM depends on several variables, including:
- Number of elements in the DOM: A DOM with more than 1,500 elements can start to negatively impact performance.
- DOM depth: The more deeply nested the HTML structure is, the longer it takes for style calculations.
- Number of child elements per node: A high number of child elements under a single node (e.g., the
<body>tag) can slow down page rendering.
Effect on Metrics like Total Blocking Time (TBT)
Metrics such as Total Blocking Time (TBT), which is a key component of performance scores, are directly affected by a large DOM. A voluminous DOM results in more expensive style recalculations and layout reflows, which delay interaction readiness.
This impact is more pronounced on mobile scores, where resource limitations are more significant.
5. Additional Metrics: FCP, SI, TBT
In addition to the Core Web Vitals, it’s crucial to monitor other performance metrics:
- First Contentful Paint (FCP): Time taken for the first piece of content to load.
- Total Blocking Time (TBT): Time during which the main thread is blocked from responding to user inputs.
- Speed Index (SI): How quickly content is visibly populated during page load. This metrix is fully dependent of the server quality and is influenced a lot by TBT.
03. Accessibility:
Ensuring Inclusivity for All Users
Accessibility ensures that your website is usable by everyone, including users with disabilities. Improving Core Web Vitals for Wordpress performance is great but improving accessibility involves adhering to standards such as WCAG (Web Content Accessibility Guidelines). Here’s how you can approach accessibility optimizations:
Key Areas of Accessibility Optimization:
- [ARIA] Attributes: Ensure that ARIA roles and attributes are valid, correctly used, and not misspelled. They should match their intended purpose and be compatible with the elements they’re applied to, like
role="button"orrole="dialog". - Alt Text and Labels: All images should have clear alt text, and all buttons, links, and form elements should have discernible labels for screen readers.
- Heading Hierarchy: Proper heading structure, with titles in a sequentially descending order, is crucial for accessibility and SEO.
- Color Contrast: Ensure that the contrast between background and foreground colors meets WCAG standards for readability.
- Language and Forms: The
<html>element must include a valid language attribute, and form elements must be properly labeled for screen readers to navigate.
Accessibility Challenges:
- Non-code Adjustments: Improving contrast ratios, adding alt text to images, and making sure buttons and links have discernible names can often be done without modifying the site’s code.
- Code-Based Adjustments: More complex issues like improper use of ARIA roles or missing form labels often require development work. In many cases, you may need to audit existing code to ensure it complies with accessibility standards like WCAG.
Addressing these areas improves not only compliance but also user experience, leading to lower bounce rates and higher engagement.
04. Best Practices:
Ensuring Efficiency and Security
Best Practices in web development cover a range of areas including performance, security, and mobile compatibility. When building or optimizing Core Web vitals for WordPress, adhering to these guidelines ensures that your site runs efficiently, is secure, and provides a smooth user experience across all devices.
Key Areas to Focus On:
- Mobile Optimization: Ensure that your site does not rely on outdated technologies or practices that hinder mobile performance. For example, avoid setting
[user-scalable="no"]in the viewport meta tag, as this limits user control over zoom, which is essential for accessibility. - Security Best Practices: Implementing HTTPS, securing cookies, and avoiding unnecessary use of risky ARIA roles will protect users and instill trust in your site.
- Valid Code and Semantic HTML: Using valid ARIA roles, semantic elements (
<header>,<article>,<footer>), and avoiding deprecated tags improve both performance and SEO by making your website easier to crawl for search engines and more efficient for browsers to render. - Document Structure: Ensure proper use of
<title>,<html lang>, and<meta>tags to define the site’s structure, improve SEO, and enhance accessibility.
Following best practices doesn’t just ensure a smoother user experience—it also improves your website’s SEO rankings and security, fostering a trustworthy environment for visitors.
05. Tech SEO:
Optimizing for Search Engines
A well-optimized website is not only fast and secure but also visible in search engines. SEO optimization goes hand-in-hand with Core Web Vitals for WordPress to boost a site’s discoverability and ranking.
Key SEO Optimizations:
- Meta Tags: Every page should have a unique
<title>element and meta description that clearly describes the page’s content. - Crawlability: Ensure that none of your important pages are blocked from being indexed by search engines. Files like
robots.txtmust be correctly configured to allow search engine bots to crawl your site. - Descriptive Links: Links should have clear, descriptive text that tells both users and search engines what the destination page is about.
- Structured Data: Implementing schema markup like
hreflangorrel=canonicalhelps search engines understand the context and structure of your site, enabling better ranking and appearance in rich snippets.
SEO is not a one-time task. Regular updates to your content, link strategy, and technical infrastructure are required to maintain a competitive edge in search results.
06. Responsiveness is not enaugh:
Mobile Score vs. Desktop Score
1.Mobile Core Web Vitals:
Challenges: Mobile devices have varying screen sizes, slower processing power, and less robust network connectivity compared to desktop systems. This makes metrics like LCP and FID more difficult to optimize on mobile.
Responsiveness Isn’t Enough: Many developers rely on responsive design principles to make their websites mobile-friendly. However, being responsive does not necessarily mean the site is mobile compliant. True optimization for mobile often requires creating a separate version of the site or optimizing elements like images and fonts specifically for mobile. This includes lazy loading images, reducing third-party scripts, and using modern image formats like WebP to ensure fast load times.
Complex Layouts: Dynamic elements, such as sliders or carousels, might work well on desktop but perform poorly on mobile devices due to slower processing power. Even if a design is responsive, excessive dynamic content can increase CLS on mobile devices, creating a poor experience for users.
2. Desktop Core Web Vitals:
Performance on Desktop: Desktop sites generally benefit from faster internet connections and higher processing power, meaning LCP and FID scores are easier to optimize. However, CLS can be more challenging on desktop if the site has complex animations or uses large media files.
Demanding Metrics: Desktop sites can also be scrutinized more rigorously by Google’s algorithm for certain aspects like layout stability. Since larger screens tend to showcase more elements simultaneously, issues related to CLS may become more pronounced.
Below the same website tested for Mobile and Desktop before and after specific Core Web Vitals optimizations:
07. Why a Mobile-First Approach Is Not Enough for performance and compliance
Though Google emphasizes mobile-first indexing, optimizing for mobile goes beyond just making a site responsive. Here’s why:
Network Conditions: Mobile users often browse on slower networks, such as 3G or 4G, which means performance issues like LCP become more critical. Heavy media files or unoptimized resources can significantly slow down loading times on mobile devices.
Specialized Mobile Design: Simply making a site responsive doesn’t ensure it is optimized for Core Web Vitals. Creating a mobile-specific version of the site can often yield better results. This involves:
- Compressing images for mobile without losing quality.
- Reducing JavaScript execution time for mobile users.
- Simplifying layouts and eliminating non-essential elements to reduce CLS.
- Utilizing faster mobile fonts and icons.
Optimizing for Smaller Devices: Smaller devices are more prone to layout shifts, which impact the CLS score. Ensuring that mobile images, fonts, and ads have fixed dimensions and don’t cause shifts is key to optimizing the mobile experience.
Server Response Time: On mobile, the time it takes for the server to respond is often longer, which directly impacts FID. Reducing server response time (by using a Content Delivery Network (CDN) or improving hosting infrastructure) is essential to ensure fast interactivity on mobile devices.
08. How Can I Achieve a Perfect 100 Performance Score for My Website?
Reaching a perfect 100 performance score on Google PageSpeed Insights can be challenging, and there are two common factors that often prevent websites from achieving this score: server configuration and capacity, and crucial scripts.
1. Server Configuration and Capacity
A website’s performance is heavily reliant on its server’s speed and capacity. Even with fully optimized content, a slow server will drag down your performance score. Issues that may arise include:
- Slow server response time: If the server takes too long to process requests and deliver content, it can significantly delay the loading process. This is often due to limited server resources or poor server management.
- Inadequate hosting environment: Shared hosting environments can lead to slower performance due to resource limitations. Upgrading to managed hosting or using a Content Delivery Network (CDN) can alleviate these bottlenecks by improving resource allocation and reducing latency.
2. Crucial Scripts
Certain scripts, such as jQuery and other essential JavaScript libraries, are necessary for a website’s functionality but tend to consume significant resources:
- Render-blocking scripts: These scripts often need to be loaded early in the page rendering process to ensure the site functions properly. While deferring or delaying the loading of non-essential scripts can improve performance, crucial scripts like jQuery cannot always be deferred without breaking site functionality.
- Heavy JavaScript: Even optimized, essential scripts like these can slow down performance due to the processing time required, especially on mobile devices with lower computational power.
While 100% is theoretically achievable, server limitations and the need for essential scripts often create obstacles that make it difficult to reach the perfect score. The best strategy is to optimize what you can while acknowledging the limits posed by these factors.
What’s Stopping You from Reaching Top Scores? We’ve Got You Covered with Two Core Service Categories!
This category focuses on improving the Core Web Vitals performance metrics, particularly LCP, FID, and CLS. Techniques include server optimization, image compression, JavaScript minimization, and ensuring non-blocking resource loading. This service is ideal for clients who need a speed boost without making major code modifications.
2. Compliance Optimization (Accessibility, SEO, Security)
This service tackles the broader aspects of web optimization, including accessibility, SEO, and best practices for security. It involves detailed code audits, enhancing the site’s accessibility for users with disabilities, and ensuring SEO compliance through proper use of metadata, structured data, and crawlability improvements.
TEST Core Web Vitals
Discover your score and what you need to improve
Not sure where to start? Request a free audit and we will send you a custom quote adapted to your website and aligned to your needs.
Need some example? Check how we went from performance score 27 to performance score 96 on mobile test and triple-100 grade in Accessibility, Best Practice and SEO.
Global Optimization + Home page Performances
LCP / FCP / CLS / TBT metrix improvment
Staged optimization
No in-depth code or Plugins modification
Preloading & Preconnect setup
Minify, Defer, Agregate, Async CSS files
Minify, Defer, Async, Agregate JS files
LazyLoading Setup
Cache Setup
CDN Setup
Global Images optimization
Webp image conversion
Home Page Critical CLS
Home Page Critical CSS
Pro Plugin License for 1 year
Audit & Reporting for further “in code” improvments and plugin advices
These improvements will boost your entire site’s speed, but each page may need individual work to reach top scores. Please note, we can’t guarantee a 90+ score without first reviewing your homepage. Some in-code optimizations are always needed to get the best results, and the outcome depends on your current score and the issues that need fixing.
Extra Page
$99
One-time fee per page in addition to the home page – GET DISCOUNT for each extra pages ordered up to 10% (see the discount applied in cart)
In-Depth Optimizations + Home page Performances
LCP / FCP / CLS / TBT metrix improvment
+90 Desktop / +70 Mobile
Staged optimization
Child Theme Setup
ALL FROM ESSENTIAL + :
DOM management (Elementor div cleaning & re-code)
Manual CSS Cleaning and agregation
Manual JS Cleaning and agregation
Manual images optimizations (home page)
Adding any missing balises (images and links)
Manual Google Font optimizations
Manual Icons libraries Optimization
CLS < 0.02
Code Structural Changes with your approval
2 Pro Plugin License for 1 year
In-Depth Audit & Reporting with plugins & hosting recommandations
We will review your website and explain all the changes needed before making any code modifications and updates. We work on a copy of your WordPress site (staged), so there’s no risk of breaking anything. The new version will go live once you approve it.
Extra Page
$149
One-time fee per page in addition to the home page – GET DISCOUNT for each extra pages ordered up to 10% (see the discount applied in cart)
Home page Compliance Triple-100 Grade
Accessibility 100
Good Practices 100
SEO Metrix 100
Staged optimization
Child Theme Setup
We will conduct a detailed audit and manually fix any critical issues in the three key categories.
Re-Code and structure update
100% WCAG compliant
Code Structural Changes with your approval
In-Depth Audit & Reporting
We will review your website and explain all the changes needed before making any code modifications and updates. We work on a copy of your WordPress site (staged), so there’s no risk of breaking anything. The new version will go live once you approve it.
Extra Page
$149
One-time fee per page in addition to the home page – GET DISCOUNT for each extra pages ordered up to 10% (see the discount applied in cart)