Blogging Guide

What Are CSS Files?

CSS (Cascading Style Sheets) are files that describe how HTML or XML elements are displayed on the webpage. These files describe everything from the layout to the style of the contents of the webpage. 

Now these files are important for displaying any webpage, but it is the unused and extraneous CSS files that are the issue here. Just like with unused JavaScript files, having unused CSS files can slow down the loading speed of your page and decrease PageSpeed.

Now let’s discuss why it is important to remove unused JavaScript and CSS files and how to recognize and locate unused JavaScript files and CSS files.

Why Should You Remove Unused JavaScript and CSS Files?

Unused JavaScript and CSS files are typically useless and can only slow down your website and stall the web page loading process.

This is why it is beneficial to examine your website and locate unused JavaScript and CSS files that may be slowing down your website.

You’ll want to be careful when removing unused JavaScript and CSS files however, as while most of the time these files are useless, sometimes removing them can mess up a web page. It is important to practice this step in a staging environment.

Let’s break down the process of locating and removing unused JavaScript and CSS Files.

How To Find Unused JavaScript and CSS Files

Finding unused JavaScript and CSS files can be tricky at first, but fortunately there are some helpful tools out there that can assist with highlighting unused code.

The Coverage tab in Google DevTools can assist with discovering unused JavaScript Files.

1. Go to the web page you want to investigate
2. Open the coverage tab in Google DevTools can assist with discovering unused JavaScript Files
3. Filter the list to show only JavaScript and CSS code
4. Filter for unused bytes
5. Inspect the code for unused JavaScript and CSS files

After following the above instructions, you should be able to see all of the various unused JavaScript and CSS files on your website. However, you’ll want to now use a plugin to reduce or remove the files.

How To Remove Unused JavaScript and CSS Files

There are two primary methods for removing unused JavaScript and CSS Files from A WordPress website. Both of these methods are done by utilizing a plugin.

Method 1: Premium WordPress Plugin

1. Access the WordPress toolbar
2. Select “Plugins” on the WordPress Sidebar
3. Search for and select WP Rocket
4. Access Rocket WP from the WordPress sidebar
5. Configure the plugin to reduce unused JavaScript files and delete unused CSS files

WP Rocket is a great plugin because it does all of the complicated work for you. Additionally, WP Rocket has other functionalities that help with PageSpeed. It doesn’t end with just removing unused JavaScript and CSS files. So be sure to explore the other options WP Rocket has to offer.

Method 2: Free WordPress Plugin

1. Access the WordPress toolbar
2. Select “Plugins” on the WordPress Sidebar
3. Search for and select Asset Cleanup
4. Access Asset Cleanup from the WordPress sidebar
5. Configure the plugin to reduce unused JavaScript files and delete unused CSS files

Using a free plugin like Asset Cleanup can definitely get the job done, but there are typically limitations. These limitations include how much or how often you can reduce unused code, and whether or not the plugin can only reduce unused code, not remove it entirely. You’ll have to upgrade to Asset Cleanup Pro or another premium plugin if you want to fully remove unused code.

*Note: While you can use multiple optimization plugins at once, be sure that none of your plugins have overlap. For example: If WP Rocket is being used to reduce unused JavaScript files, make sure no other plugin is configured to perform that same task.

Now let’s jump into one of the more tempting PageSpeed mistakes a new website owner can make.