Improving Site Performance

Learn why site performance is important for all WordPress sites, and learn tips to improve it.


At the end of this lesson, you will be able to:

  • Recognize the factors that affect WordPress site performance.
  • List the ways you can improve WordPress site performance.

 Prerequisite Skills

You will be better equipped to work through this lesson if you have experience in and familiarity with:

Screening Questions

  • Do you have a self-hosted website (vs. website)?
  • Have you installed plugins before?

Teacher Notes

  • The preferred answers to the screening questions is “yes.” Participants who reply “no” any questions may not be ready for this lesson.
  • You may print out the Hands-On Walk-through part to use it as handouts or send it out as a .pdf file to keep it green and preserve the links used throughout the document.
  • It might make sense to have a discussion based on the first part of the walkthrough to access what criteria of site performance & methods to improve it students are familiar with already.

Hands-on Walkthrough

What is WordPress site performance?

WordPress site performance is characterized by how fast pages on the site load. There are several reasons why performance matters:

  • Better performance brings better visitor/customer experience
  • Google and other search engines rank sites based on performance so that they rank sites with better performance higher
  • Adequate site response site helps to decrease bounce rate, the rate at which users “bounce off” your site and go somewhere else

There are some pretty impressive statistics regarding website performance (source):

  • 40% of people abandon a website that takes more than 3 seconds to load.
  • A one-second delay in page response can result in a 7% reduction in conversions.
  • 47% of consumers expect a web page to load in 2 seconds or less.

So it makes sense to invest some time to ensure your site is optimized and performs well.

How to measure site performance

Now that you know why site performance is important, it’s time to discuss how it’s measured and how can you check your site speed – and get a benchmark measurement before you start working to speed it up. You could ask a friend to take a look on how fast your website loads. However, a more efficient way would be just to use one of the sites which provide speed measurement services. Among most popular is Google PageSpeed which is an excellent way to measure your WordPress site’s performance on different devices and obtain specific feedback on what should be improved.

What can impede performance?

When your website visitor’s device requests data from a website hosted on a server somewhere, there are two primary bottlenecks that may slow down data that’s being transferred between your server and your visitors:

  • Host – the kind of hosting you choose has a great impact on your site’s speed. If you’re using shared hosting, the hosting company manages it, and you don’t have much control over it. A hosting company with good reviews and decent prices is generally OK for beginners and non-critical websites. If you decide to have a dedicated server to host your site, the number of servers and hardware used will be something to pay attention to.
  • Network – sometimes the network your visitor uses to access your site is not ideal. And even if it’s good, if your site has a lot of content, it will take time to process and load it. Most optimizations this lesson plan explores strive to reduce the amount of data transferred over the link between a server and a client with each refresh of the page.

How to optimize your website?

There are several popular ways to get a performance boost out of a website.


Caching is the process of storing data from previous requests to be re-used for subsequent requests. Caching prevents repeating database requests that transfer the same data over and over. It stores some of the information that has already been requested for and so it can be instantly served to the client as a complete page. This saves the processing time of recreating a page repeatedly. Caching also minimizes server load. Normally, when a visitor comes to your site, WordPress executes one or more (and often many) MySQL queries and PHP scripts to locate a requested page. Then the requested resources are parsed and PHP generates a page to display to the visitor, using server resources. With page caching on,  you can skip all that server load and display a cached copy of the page as soon as it’s requested, as long as it is available in the cache. There are plenty of caching plugins available, such as W3 Total Cache, which allows browser, page, object and database caching. Some of the most popular alternatives are W3 Super Cache, which has fewer options to customize so may feel less overwhelming, and WP Rocket, which is an efficient but quite simple premium plugin. And there are many other caching plugins.


Another way to approach the server load problem and increase the speed of content delivery is to offload part of the content to other servers. One can use a CDN for this. CDN stands for Content Delivery Network. A CDN is a network of servers, usually located at various sites around the world. These powerful servers can cache the static content of a site, such as image, CSS, and JavaScript files, so that when a visitor lands on your site, the content is provided by the server closest to their location. Popular CDN providers include CloudFlare, Amazon CloudfrontMaxCDN, and KeyCDN. You can also outsource hosting of your static content and RSS feeds.

Optimizing your site’s configuration

The theme and plugins that you use on a site are very important for the site’s performance. A fast, lightweight theme will perform much better than a heavy graphic-laden theme. And if you have a lot of plugins activated, that may also take a toll on performance. So you need to make sure all the plugins you don’t need are deactivated and deleted.


You also can minify your content so that your pages are delivered more quickly to readers’ browsers. For example, the W3 Total Cache plugin mentioned earlier includes the minify module which controls whether HTML, CSS, and Javascript files are minified and compressed. Minification removes all unnecessary or redundant data from the code without affecting performance, minimizing the size of the file that needs to download to the user’s browser. This causes website pages to load faster and generally speeds up site operation. Plugins such as WP Smushit or EWWW Image optimizer plugins are a good choice to compress your images and other media files.


Your site or blog’s performance is very important for its visitor experience and for the ranking it gets from search engines. The pillars for improving the site speed are:

  • choosing a reliable and powerful hosting
  • enabling caching and compression
  • making sure your site uses lightweight theme and is not overloaded with plugins
  • possibly using external services to offload part of your bandwidth


Why is low performance bad for your site (choose as many as applicable)?

  1. It shows content that you may not want your readers to see
  2. It distorts the visitor experience
  3. It could hurt your SEO
  4. It makes you pay more for the hosting of your website

Answer: 2. It distorts the visitor experience & 3. It could hurt your SEO

Which of the following is a valid way for you to increase your site’s performance?

  1. Install and configure a caching plugin
  2. Schedule a backup strategy for your site
  3. Keep no active plugins at your site
  4. Make adjustments to site’s Settings
  5. All of the above

Answer:  1. Install and configure a caching plugin

Additional materials

Some more details on optimizing your website can be found at WordPress Optimization/WordPress Performance section @ Codex