If you test your website on Google PageSpeed insights, then you will likely see a suggestion to eliminate render-blocking scripts and CSS. However, it does not provide any details on how to do that on your WordPress site.
A user’s browser will have to load those scripts and CSS before loading the rest of the HTML on the page. This means that users on a slower connection will have to wait a few milliseconds more to see the page.
WordPress website owners who are trying to achieve a Google PageSpeed score of 100 will need to fix this issue to attain that perfect score.
What Is a Google PageSpeed Score?
Google PageSpeed Insights is a website speed test tool created by Google to help website owners optimize and test their websites. This tool tests your website against Google’s guidelines for speed and offers suggestions to improve your page load time.
It shows you a score based on the number of audits that your site passes. Most websites get somewhere between 50-70. However, some website owners feel compelled to achieve 100 (the highest a page can score).
Do You Really Need the Perfect “100” Google PageSpeed Score?
The purpose of Google PageSpeed insights is to provide you with guidelines to improve the speed and performance of your website. You are not required to follow these rules strictly.
Remember that speed is only one of the many website SEO metrics that help Google determine how to rank your site. Speed is so important because it improves user experience on your site.
A better user experience requires a lot more than just speed. You also need to offer useful information, a better user interface, and engaging content with text, images, and videos.
Your goal should be to create a fast website that offers a great user experience.
We recommend that you use Google PageSpeed rules as suggestions. If you can implement them easily without ruining user experience, then that’s great. Otherwise, you should try to do as much as you can, and then don’t worry about the rest.
Method 1: Fix Render Blocking Scripts and CSS With WP Rocket
For this method, we will be using the WP Rocket plugin. It is the best WordPress caching plugin on the market that allows you to quickly improve your website performance without any technical skills or a complicated setup.
WP Rocket works out of the box, and it will turn on caching with optimal settings for your website. You can learn more about it in our complete guide on how to properly install and set up WP Rocket in WordPress.
To do that, you need to visit the Settings » WP Rocket page and then switch to the ‘File Optimization’ tab.
From here, scroll to the CSS Files section and check the boxes next to ‘Minify CSS’, ‘Combine CSS Files’, and ‘Optimize CSS Delivery’.
Note: WP Rocket will attempt to minify all your CSS files, combine them, and only load the CSS needed for the visible part of your website. This could affect your website’s appearance, so you need to thoroughly test your website on multiple devices and screen sizes.
You can also stop WordPress from loading the jQuery Migrate file. It is a script that WordPress loads to provide compatibility for plugins and themes using old versions of jQuery.
Most websites don’t need this file, but you will still want to check your website to make sure that removing it does not affect your theme or plugins.
Don’t forget to click on the ‘Save Changes’ button to store your settings.
After that, you may also want to clear the cache in WP Rocket before testing your website again with Google PageSpeed Insights.
On our test site, we were able to achieve a 100% score on desktop devices, and the render-blocking issue was solved in both mobile and desktop scores.
Method 2: Fix Render Blocking Scripts and CSS With Autoptimize
For this method, we will be using a separate plugin made specifically for improving the delivery of your website’s CSS and JS files. While this plugin gets the job done, it does not have the other powerful features that WP Rocket has.
Upon activation, you need to visit the Settings » Autoptimize page to configure the plugin settings.
Next, scroll down to the CSS Options box and check the ‘Optimize CSS Code’ option. Make sure that ‘Aggregate CSS-files’ option is unchecked.
You can now click on the ‘Save Changes and Empty Cache’ button to store your settings.
Go ahead and test your website with the PageSpeed Insights tool. On our demo site, we were able to fix the render-blocking issue with these basic settings.
For example, you can allow the plugin to include inline JS and remove scripts that are excluded by default, like seal.js or jquery.js. Then, simply click on the ‘Save changes and Empty Cache’ button to save your changes and empty the plugin cache.
Once you are done, go ahead and check your website again with the PageSpeed Insights tool.
How Does Autoptimize Work?
This allows you to fix the render-blocking scripts and styles issue. However, please keep in mind that it can also affect the performance or appearance of your website.
While the above tools can help, your plugins may need certain scripts at a different priority level to work properly. In that case, the above solutions can break the functionality of such plugins, or they could behave unexpectedly.
Google may still show you certain issues, like optimizing CSS delivery for above-the-fold content. WP Rocket allows you to fix that by manually adding the Critical CSS required to display the above fold area of your theme.
However, it can be quite difficult to find out what CSS code you will need to display above-the-fold content.