Page Speed Test Optimizing WordPress Sites

Guide to learn how to test page speed & performance, explore and measure results to give you best tips for optimizing your WordPress sites

By Claudio Pires
Updated on May 1, 2023
Page Speed Test Optimizing WordPress Sites

Load time is the metric that describes how long a web page takes to load. This process includes HTML and all the CSS code, scripts, images, and third-party resources found on a website. This article will explore a test of how to measure page speed and performance and give you tips for optimizing your wordPress sites.

We can define load time as the time frame between the moment a user starts navigating to the page until all of its page content has loaded. It’s a fact that, ideally, a performant page should load in less than two seconds. This is especially true for mobile pages, which suffer the most from long load times.

Page Speed Test WordPress

Running a page speed test is as easy as visiting a website and entering your website’s URL into a box. The speed test then analyzes your website and comes up with recommendations. There are many different speed test tools, but here are a couple worth looking at.

Pingdom has a tool for speed testing, and it lets you test from different locations around the world or from a server that is relatively close to you. For example, targeting a local audience is an excellent way to see how fast your website is for them.

Google Lighthouse is a Chrome browser’s Web Developer Tools performance tool. To access it, right-click on a page, choose Inspect, and check the Audits tab in the new window that opens. Here, you can test speed for mobile devices or desktops on different bandwidths and connection speeds.

Before Lighthouse came along, Google PageSpeed Insights was a great way to look for speed improvements – and it still is. It even lets you download optimized images, CSS, and JS files for your site. But if you’re working with WordPress, you may find it difficult to replace your files with these optimized files directly. Luckily, WordPress has plugins that will generate them for you.

Page speed x WordPress plugins

After in measure the results and running the page speed and performance test, you probably feel like you should spend some time optimizing your WordPress sites for speed. You’ll get many recommendations, from things you can do yourself to things you might need technical help with.

Optimize Images in WordPress

WordPress has a handy default feature where every image you upload is stored in several sizes. So if you want all the images in your posts to be the same width, pick one of the predefined ones or set your custom dimensions. This means that if, for example, you load the medium size image instead of the much larger original, this will serve an image in a smaller file size, which will load much faster.

There are also several image optimization plugins (both paid-for and free) available for WordPress, such as Kraken.ioSmush, or Imagify. Plugins usually remove Exif data from the image, which is a good idea because Exif data includes information about the camera settings used to take the photo.

Some of these plugins can also help you resize your images. Take these plugins for a test drive and see which works best for you and minifies your image files best. To find out more about image optimization, be sure to check this post about image SEO.

Cache On Browser

Another issue that comes up a lot in page speed tests is browser cache optimization. Browser cache is about storing website files, like JS and CSS, in your local temporary internet files folder to retrieve them quickly on your next visit. Or, as Mozilla puts it: The Firefox cache temporarily stores images, scripts, and other parts of websites you visit to speed up your browsing experience.

WP Super Cache

Most speed optimization plugins help you to optimize your site using caching. Sometimes it’s as simple as this: Advanced tab of WP Super Cache here has a lot of more in-depth configuration for that, but starting with the set defaults of a plugin is usually a good start. After that, start tweaking these advanced settings and see what they do.

Other WordPress Caching Plugins

I’m talking about WP Super Cache here because it’s free and easy for most people. But there are alternatives. WP Fastest Cache is popular as well, with over 600K+ active installs. It has similar features to optimize caching.

A paid-for plugin I also like is WP Rocket. Configuring is easy, and you’ll wonder whether you have missed something. But your page speed test will tell you it works out of the box. In addition, there are more advanced settings where you can fine-tune your site. But before we look at that, we need to talk about compression.

Compressing Files

Your page speed test tool will probably tell you to Try to minify your CSS files. Minify the JS files of your site. Minify your HTML files or enable (GZIP) compression.

These recommendations all relate to compression. It’s about making your files as small as possible before sending them to a browser. It’s similar to reducing the file size of your images but for JavaScript or CSS files or even a page’s HTML file. GZIP compression sends a zipped file to your browser that your browser can unzip and read. Your speed test’s recommendations may look like this:

Again, many right settings are on by default, similar to Yoast SEO, but even more can be configured to your needs. Your web server’s settings may also affect how well compression works.

If you use one of these plug-ins, do the test on how to measure page speed and performance so you are optimizing your wordpress sites. But your compression optimization is still not working properly. Contact your hosting company and see if they can help you. A decent host should be able to help you, especially if it is one of these WordPress hosting companies.


Speed tests often tell you to combine (external) CSS or JavaScript files or defer parsing scripts. These recommendations concern how these files are served to the browser.

As you can see in the WP Rocket screenshot above, the combined option for these files is not recommended for websites that use the HTTP/2 protocol, which allows multiple script files to be loaded simultaneously. But combining these files is still good for non-HTTP/2 sites because it reduces the number of server requests, making your site faster.

Deferring scripts or recommendations like “Eliminate render-blocking JavaScript and CSS in above-the-fold content” are about the way these scripts are loaded in your template files. If all of these are served from the top section of your template, your browser will wait to show (certain elements of) your page until these JavaScript and CSS files are fully loaded.

Sometimes it pays to transfer less-relevant scripts to the footer of your template, so your browser will show your website first and then add the enhancements controlled by JavaScript or CSS files. A plugin that can help you with this is Scripts-to-Footer. Warning: test this carefully. Changing the way that these files load can impact your website. Things may suddenly stop working or look different.

Speed Test and CDN

A Content Delivery Network caches static HTML, CSS, JavaScript, and image files. These files don’t often change, so we can serve them from a CDN with many servers worldwide so you can get them to your visitors super fast.

It’s like traveling: the shorter the trip, the faster you get to your destination. The same goes for these files. If the server serving the static file is located near your visitor, the site will load faster for that visitor. See this post for more about CDNs.

Conclusions of Page Speed Test WordPress

But in the end, if you want a fast website, WordPress is a great choice because many great plugins can help you optimize the speed of your website after a page speed test! So we hope this article about a test of how to measure page speed and performance and gives you tips for optimizing your wordPress sites has helped you!

Claudio Pires

Claudio Pires is the co-founder of Visualmodo, a renowned company in web development and design. With over 15 years of experience, Claudio has honed his skills in content creation, web development support, and senior web designer. A trilingual expert fluent in English, Portuguese, and Spanish, he brings a global perspective to his work. Beyond his professional endeavors, Claudio is an active YouTuber, sharing his insights and expertise with a broader audience. Based in Brazil, Claudio continues to push the boundaries of web design and digital content, making him a pivotal figure in the industry.