JavaScript is already a challenge for rendering content, and now search engines are having a problem to “Eliminate render-blocking resources”.
It will display a blank page. Furthermore, unless you alter it, the browser will keep this state (blank page) for as long as it finds render-blocking resources.
Everyone needs to resolve or remove render-blocking resources from your website. This may sound complicated, especially if you’re unfamiliar with the term.
Simply put, render-blocking resources are files on your website that slow down its loading speed, which can harm its performance. This is a problem because it affects how visitors view your site and can impact its ranking on search engines like Google.
To prevent this, we’ll provide step-by-step instructions on how to remove render-blocking resources in WordPress. You’ll learn what they are, how to identify problematic files, and how to fix them.
So, let’s get started!
What is “Eliminate render-blocking resources”?
Simply put, render-blocking resources are website files that hinder the quick loading of web pages. To understand this, let’s delve into how the loading process works.
When a visitor opens one of your web pages, their browser starts processing the page’s HTML code. Along the way, it encounters requests for other files like CSS style sheets and JavaScript scripts. These files add style and interactivity to web pages.
However, when the browser comes across these files, it needs to download and process them. During this time, it can’t at the same time continue rendering the page. This pause in loading results in longer wait times for website visitors.
While this is a normal part of website functioning, some files hinder the browser’s work without actually contributing to the page being loaded.
For instance, tracking scripts like those for Google Analytics or Facebook Pixel, while important, can slow down loading if not timed correctly. These files are what we refer to as render-blocking resources—they stall the loading process unnecessarily.
Typically, render-blocking resources are CSS or JavaScript files, though other files like font files or images can also impede page loading. Although these files are essential for a website’s design, it’s crucial to optimize them for quick loading as well. We’ll discuss optimization strategies further below.
What causes it to be “Render-blocking resources”?
StyleSheets and JavaScripts are always render-blocking assets located in the page’s head. This indicates that your site developer can only manually add them using a plugin or through your CMS.
Try looking in the following locations when attempting to locate the source of a render-blocking resource:
- The first place to check is your website’s template files. Locate the code and search for scripts and styles that are hardcoded.
- At times, certain scripts (like jQuery) are necessary for the CMS to function correctly.
- Plugins are famous for introducing scripts and styles into websites.
Working Process of Critical Rendering Path
The steps taken by a browser to render a page—from HTML, CSS, and JavaScript to actual pixels on the screen—are referred to as the critical rendering path.
The sequence of actions a browser takes to translate HTML, CSS, and JavaScript into actual pixels on the display is known as the “critical rendering path.”
Before rendering any visual content, the browser must essentially request, receive, and parse all HTML and CSS files (plus do some more work).
This process takes, for the most part, a nanosecond to complete. Until the browser carries out these actions, users will see a blank white screen.
An illustration of how viewers could perceive a page’s loading speed based on its various phases is shown below:
Source: Render
Thus, optimizing the crucial rendering path can enhance the user experience on the page as a whole, benefiting Core Web Vitals metrics performance.
How to Solve ‘Eliminate Render-Blocking Resources’ Issue?
To fix the problem of ‘render-blocking resources’, you need to ensure these resources don’t block rendering anymore.
The easiest method is to remove them altogether. Sometimes, old and unused resources still obstruct the page’s rendering. If removal isn’t feasible, you should defer them.
- Defer Elements
Defer JavaScript
You can defer JavaScript by adding the ‘defer’ or ‘async’ attribute to the script tag.
<!-- Deferred JavaScript --><script defer src="script.js"></script><!-- Asynchronous JavaScript --><script async src="script.js"></script>Defer StyleSheets
Deferring style sheets can be more complex. When a stylesheet is deferred, the page initially renders without styles. Later, when the styles load, the browser applies them, causing flickering and layout shifts. To mitigate this, you’ll need to use inline critical CSS. Critical CSS contains the styles necessary to render the visible part of the page.
<style>// Critical CSS here</style>
<link rel=”preload”
href=”css.css”
type=”text/css”
as=”style”
onload=”this.onload=null;this.rel=’stylesheet’;”/>
- Use Conditional CSS with the Media Attribute
When you use the media attribute with the <link> tag in your HTML, you can control how CSS files are treated by the browser based on certain conditions.
By default, CSS files are treated as something that must be loaded before the page can be displayed.
But with the media attribute, you can make them load only under certain conditions, like when the screen is being printed or when the screen size matches a specific range.
For example:
<link href=”print.css” rel=”stylesheet” media=”print”>
<link href=”large.css” rel=”stylesheet” media=”screen and (min-width: 1500px)”>
<link href=”mobile.css” rel=”stylesheet” media=”screen and (max-width: 600px)”>
These CSS files will still be downloaded on all devices, but they won’t block the rendering of the page unless the conditions specified in the media attribute are met.
For instance, the mobile.css file will block rendering on devices with small screens (up to 600px wide), but won’t block rendering on larger screens.
If you want to separate your existing CSS file into multiple files based on different conditions, you can use a tool like a PostCSS plugin to do that.
- Reduce the Size of CSS and JavaScript
You can additionally compress both render-blocking and non-render-blocking resources. Because minified files are lighter, initial page rendering will be faster. Furthermore, it will take less time to download non-render-blocking resources in the background.
CSS Minifier, Minify Code, and PostCSS (minify plugins) are some of the tools available to help you do minification in accordance with best practices. Build technologies such as Webpack, Parcel, and Rollup include built-in minification capabilities that allow you to easily reduce the weight of render blocking resources.
Also Read: How to Optimize your WordPress Code using Minification and Concatenation
Implement other Optimization Techniques
Other than removing render-blocking resources from your WordPress site, there are more ways you may use to optimize its performance:
- Caching – Caching is the process of saving static copies of your web pages as HTML files on your server. This eliminates the need to dynamically generate them from PHP files and the database each time a web page is requested.
- Image optimization – While images are not render-blocking, they have a significant impact on page loading performance and should be optimized as well. Compression, selecting the correct size, and utilizing contemporary picture formats such as WebP and Avif all help to reduce image size and speed up delivery. Image optimization is particularly crucial for mobile devices.
- Lazy loading – Another way to optimize images. It instructs browsers to only load images that appear on the screen first, deferring those lower down the page until the user scrolls toward them. This saves a great deal of bandwidth.
- Database optimization – The database includes all of your website’s content. If it is slow due to redundant data, it affects the entire website. This is why it requires regular optimization and cleansing.
Also Read: 5 Best Code Optimization Plugins for WordPress
Final Say
Optimizing your website’s Core Web Vitals by identifying and removing render-blocking elements is critical for enhancing user experience and search engine rankings.
Understanding how render-blocking resources affect loading times and using solutions such as asynchronous loading, postponing JavaScript, and optimizing CSS delivery can greatly improve your website’s performance.
Regular monitoring and testing are required to discover and address any likely issues, ensuring that your website provides a fast and flawless experience for all visitors.
FAQs on Eliminate Render-Blocking Resources
How can I identify render-blocking resources on my website?
To identify you can use tools like Google PageSpeed Insights, Lighthouse, or GTmetrix to identify render-blocking resources on your website and get recommendations for optimizing them.
What are some techniques for eliminating render-blocking resources?
Some techniques for eliminating render-blocking resources include:
- Asynchronous loading of JavaScript files
- Deferring JavaScript execution until after the page has finished rendering
- Optimizing CSS delivery by minimizing and combining CSS files
- Using inline CSS for critical above-the-fold content
- Leveraging browser caching and CDNs to reduce server response times
Is it necessary to eliminate all render-blocking resources?
While it may not be possible to eliminate all render-blocking resources, minimizing their impact on page loading times is essential for improving Core Web Vitals and overall user experience.
How often should I check for render-blocking resources on my website?
It’s recommended to regularly monitor and test your website’s performance using tools like Google PageSpeed Insights or Lighthouse to identify and address any issues with render-blocking resources.
