Speed up your site with a caching plugin

Editor’s Note: We’re reviewing ways to speed up your site and improve your PageSpeed score. Learn how image optimization impacts your score here.

One of the best things you can do for your WordPress blog is to install a caching plugin. We strongly believe that a caching plugin is essential for sites of all sizes. Before you brush it aside as being too technical, check out the very simple options below. Your readers and your wallet will thank you!

You need a caching plugin

WordPress is a workhorse, doing everything from pulling content from your database, running your plugins, and building the content to displaying the resulting screen for the person visiting your site. Each request from your visitors requires server resources (e.g., things like processing power and memory).

When enough visitors are visiting the site at the same time, the server simply doesn’t have enough resources to keep up and will effectively force people to wait their turn before it can respond. This can result in your site loading slowly for visitors.

A caching plugin takes advantage of all the work your server does to generate a post the first time it’s requested and then saves the result to a static file. The collection of these static files is called a cache. Your site can then serve that static file to subsequent visitors rather than tying up resources to regenerate the same post over and over. The end result? Better bang for your buck on your hosting and a much quicker site for your visitors!

Plugin reviews

As with other site speed optimizations, there are several excellent WordPress plugins to help speed up your site this way. We’re going to take a look at our favorites today.

Both of the plugins reviewed below are simple to install and configure.

WP Super Cache is a free plugin that works great, but you’ll want to pair it with Autoptomize for other optimizations as well. On the other hand, WP Rocket is a paid plugin that handles several different speed optimizations without the need for additional plugins.

While they differ in approach and functionality, both plugins offer great improvement over running a WordPress site without caching. 

WP Super Cache

Key features…

• Granular configuration and troubleshooting.
• Integration with Content Delivery Networks (CDN) services.

Best pick for…

• Bloggers looking for a powerful caching tool at no cost.

With over 1 million installs, WP Super Cache (WPSC) is a popular caching plugin with a long, solid history. It provides great flexibility with numerous configuration settings, but if you simply stick with a few recommended options, there’s very little setup required.

We recommend using it in conjunction with Autoptimize for the best site performance.

Recommended settings

After installing the plugin in your WordPress dashboard, press the Activate Plugin link and go to Settings → WP Super Cache. There you’ll see the tabbed sections of the plugin’s admin area.

Press the Advanced tab, then enable the settings listed below. Oddly enough, some of their Recommended settings aren’t enabled by default. Typically you can start by enabling the following options, which are not set initially:

• Cache hits to this website for quick access.
• Use mod_rewrite to serve cache files.
• Don’t cache pages for known users.

The “Don’t cache pages for known users” option is worth a quick explanation. That ensures that when you are logged in with WordPress, you will bypass the cache and see the dynamic pages when browsing the site. This can be helpful for WordPress administrators to see updates immediately without having to clear the cache.

Press the Update Status button to save your choices.

Next, you’ll likely see a banner stating, “Warning! Garbage collection is not scheduled!” Press the link to scroll down to the Expiry Time & Garbage Collection section. This setting determines how often WordPress will look for expired items in your cache that need to be refreshed. If you’re unsure what to choose, select Timer and 3600 seconds. Scroll to the bottom and press Change Expiration.

That’s it!

Confirming cache

To confirm the cache is working, go to Easy and press the Test Cache button. You can also confirm a page is served from cache viewing the page source in your browser.

To do that, log out of your dashboard and visit your site. Right click and select View Page Source. Scroll to the bottom, and you should see this code:

<!-- Dynamic page generated in 0.118 seconds. --> <!-- Cached page generated by WP-Super-Cache on 2019-02-23 19:54:27 -->

Additional options

WPSC also works with CDNs, if you’re using such a service with your site.

If you’re needing to dig deeper, there are numerous configuration tweaks available throughout the other sections of the WPSC admin area. You can also view the status of the cache, and use the the logging information under Debug if you’re having problems.

WP Rocket

Key features…

• Caching plus CSS, HTML, and JavaScript minification in one plugin.
• Integration with Content Delivery Networks (CDN) services.
• Lazy load option for images to improve the performance of image-heavy sites.

Best pick for…

• Professional bloggers who are ready to invest in a plugin with advanced features.

WP Rocket is a premium plugin offering powerful cache and optimization features. It works right out of the box and handles the tasks of several different plugins in one. Plus it integrates with other popular services, like Cloudflare and Facebook Pixels, for top performance.

Recommended settings

Because this is a premium plugin, you’ll receive a ZIP file after purchase, which you’ll upload to your dashboard and then click Activate. The plugin will work automatically once you activate it, but there are a few things you can adjust to maximize its performance.

To start, if you have the Autoptimize plugin installed, you’ll want to Deactivate it. Once you’ve made sure everything is working correctly, you’ll be able to delete the Autoptimize plugin altogether. You should also clear the cache on Cloudflare or any other proxy service you use.

Next, head to Settings → WP Rocket. There you’ll see a tabbed sidebar with all of the plugin options.

Under File Optimization, ensure the following boxes are checked:

• Minify HTML
• Combine Google Fonts files
• Minify CSS files
• Optimize CSS delivery
• Minify JavaScript files
• Load JavaScript deferred
• Safe Mode for jQuery

Under Media check LazyLoad → Enable for Images.

Finally, go back to the Dashboard tab and click the Clear Cache button. (If you’re using Cloudflare or some other proxy/caching service, you’ll want to clear that cache as well.) Log out of your WordPress dashboard—or open an incognito browser window—and then click around your site to be sure everything is working as expected. If so, you should be set! If you run into errors, try unchecking the boxes on the File Optimization tab one by one, clearing the cache each time, to isolate the problem.

Confirming cache

Open the browser’s source view of the page and scroll to the bottom. At the very end you should see an entry like this:

<!-- This website is like a Rocket, isn't it? Performance optimized by WP Rocket. Learn more: https://wp-rocket.me - Debug: cached@1553532126 -->

Note: If you use Cloudflare, you won’t see this message because the HTML minification removes it.

Additional options

Visit the Add-Ons tab to explore additional integrations with Google Analytics, Cloudflare, Facebook Pixels, and more.

If you use a Content Delivery Network, click the CDN tab to enable this option. WP Rocket offers a step-by-step guide for integrating your CDN with the plugin.

What’s next?

Adding caching functionality is one of the easiest and quickest ways to speed up your site and save on server costs. Combine that with other optimization functions (optimizing your images, as well as Javascript, HTML, and CSS), and you’ll have your site running more efficiently and faster than before.

If you find that you need help selecting any of the plugins we reviewed in the series, or would like for us to handle these optimizations for you, contact Support, and we’d be happy to assist!

Share your experience!

We’d love to know which caching plugin you use and how it’s impacted your site speed and hosting costs. Drop a comment here or tweet us at @agathongroup!

Brian Pikkaart

Brian works with clients to capture and organize their priorities and budgets and then coordinates our development team to get the work done. In addition, he plays an important role in the system administration for our hosting environment.