Check your site’s performance

A fast-loading website is essential for giving visitors a smooth experience and boosting your ranking in search engines. This guide will show you how to run a performance report on your website and get WordPress-specific recommendations for improving its speed.

This feature is available on sites with the WordPress.com Business and Commerce plans. If you have a Business plan, make sure to activate it. For free sites and sites on the Personal and Premium plans, upgrade your plan to access this feature.

To test the speed of your WordPress.com website, take the following steps:

1. Visit your Sites list in the dashboard.
2. Click the title of the website you want to analyze.
3. Click on the “Performance” tab to run the tests, which will take approximately 30 seconds. If you previously received a score for your site and want to generate a fresh report, you can click the “Test again” button to generate a current score.
4. After testing your website’s performance, click the “View all recommendations” link to view the AI-powered suggestions for improving your site based on its performance score.

By default, your site’s homepage will be tested. To test other pages, click on the “Page” option to select from other public pages on your site.

Your site will receive a performance score using Lighthouse, an automated tool from Google for assessing web page quality. The performance score is a combined representation of your site’s individual speed metrics, which include the following:

• First Contentful Paint (FCP) is the time it takes for the first bit of content (like text or images) to show up on the screen after someone visits your website. The best sites have an FCP of under 1.8 seconds. Learn more about FCP.
• Largest Contentful Paint (LCP) measures how long it takes for the biggest piece of visible content, like a large image or heading, to fully appear on the screen. The best sites have an LCP of under 2.5 seconds. Learn more about LCP.
• Cumulative Layout Shift (CLS) shows how much your website’s layout moves around while it’s loading, which can cause things like buttons or text to shift unexpectedly. The best sites have a CLS score of 0.1 or lower. Learn more about CLS.
• Time to First Byte (TTFB) measures how quickly your website starts to respond after someone clicks on it, showing the first sign that it’s loading. The best sites have a TTFB of around 800 milliseconds or fewer. Learn more about TTFB.
• Total Blocking Time (TBT) is how long your website is unresponsive while loading, meaning people can’t interact with it during this time. The best sites have a TBT of under 200 milliseconds. Learn more about TBT.

Your site will receive separate performance scores for mobile and desktop. Click the “Mobile” and “Desktop” buttons in the upper corner to view your site’s performance scores and recommendations on each device.

Click on a recommendation to read an explanation of the problem, suggested solutions, and a list of URLs affected by that performance issue (which could include image URLs or files). These recommendations are tailored to your website so you can take action to improve your site’s performance.

Below are some of the most common methods you can use to improve a site’s performance score. These recommendations are actionable steps for site admins to take, knowing that your site is also optimized at the host level.

You can install Jetpack Boost, a free plugin with these beginner-friendly options to improve site performance:

• Optimize CSS loading: Load only the styling code that is needed first.
• Defer non-essential JavaScript: Delay scripts that aren’t needed immediately upon page load.
• Optimize images: Deliver images using a global CDN to ensure they load quickly.

These options can significantly help with LCP (Largest Contentful Paint), reduce TBT (Total Blocking Time), and improve interactivity.

Large image files can load slowly in your visitors’ browsers. Often, images are uploaded larger than they need to be, and can be resized down while still appearing in high quality on your site.

Visit our Optimize your images guide to learn how to ensure your site’s images are sized appropriately to help them load faster.

Your site’s theme plays a big role in performance. Some themes are visually stunning but packed with heavy code, large images, and extra scripts that slow down loading. Switching to a lightweight, performance-optimized theme can improve FCP, LCP, TBT, and even TTFB by reducing the amount of data the browser has to process.

Before you make the switch on your live site, try a new theme on a staging site to activate the new theme privately and compare before-and-after results to see if the change truly improves performance.

Every plugin you activate adds extra code that your site has to load. Some plugins are small and efficient, while others can significantly slow down TTFB, LCP, and TBT by adding scripts, styles, or database queries.

Optimize your site’s plugins with the following steps:

1. Check your active plugins: In your site’s dashboard, navigate to Plugins to see the site’s currently active plugins.
2. Delete unnecessary plugins: If a plugin adds a feature you no longer use (or that’s built into WordPress.com itself), it might be safe to remove it.
3. Test performance without a specific plugin: You can temporarily deactivate a plugin and run a new performance test to see if your site’s performance score improves. If it does, it’s a sign that the plugin was likely negatively impacting your site’s performance.
4. Try new plugins on a staging site: Test every new plugin on a fresh staging site to check how it affects performance.
5. Install one plugin at a time: Installing multiple plugins at once makes it difficult to determine which plugin is compromising performance.
6. Update your plugins regularly: Regular updates ensure your site includes the latest performance optimizations from the plugins’ developers. WordPress.com includes automatic plugin updates and scheduled plugin updates.
7. Replace heavy plugins with lighter alternatives: Sometimes you can get the same functionality from a faster, simpler plugin.

Keeping your plugin list lean helps your site load faster, respond more quickly to user input, and stay stable across both desktop and mobile.

You might receive advice to install page caching on your website. But WordPress.com has caching built in, so installing a caching plugin is not necessary and can even compromise the existing caching functionality and page load time. 

Built-in WordPress.com caching will always be faster and more efficient than any page-caching plugin, so leave your page caching to us at the server level. While troubleshooting, you can clear your site’s cache in the settings or by using WP-CLI via SSH.

Even though WordPress.com provides lightning-fast hosting, performance can still suffer if your site uses heavy themes or lots of plugins. Try to:

• Use a lightweight theme, such as those recommended in the theme showcase or a third-party theme that is well-reviewed.
• Use fewer plugins, especially resource-intensive ones that have negative feedback ratings from other users.

These actions help reduce TTFB and improve the speed of content rendering and LCP.

Unexpected shifts in layout frustrate visitors. To reduce Cumulative Layout Shift (CLS):

• Use a well-structured theme, such as those recommended in the theme showcase or a third-party theme that is well-reviewed.
• Avoid embedding content that loads unpredictably (like ads or large embeds)

This helps your site stay visually stable as it loads.

Optimizing a WordPress site’s database can improve its performance and efficiency. As the database grows with content, comments, user data, and plugin-related data, it can become bloated and slow, leading to longer query times and increased server load.

Here are several strategies to effectively optimize your WordPress database:

• Remove unused data like drafts and spam comments to help keep the database lean and fast. 
• Delete old and unused plugins and their data to further reduce clutter and improve performance.
• Optimize database tables through phpMyAdmin to improve access speed. Adding custom indexes to columns frequently used in search queries or JOIN operations can also significantly speed up query performance. However, this should be done by experienced developers only, as improper indexing can actually increase the database size and degrade performance.

Performance isn’t a one-time task. Regularly check your site’s performance score to:

• Track metrics over time.
• See how performance improvements (like image optimization or plugin removal) affect results.
• See how additions to your site (like installing a new plugin or changing the theme) affect resutls.

And remember, a perfect score of 100 is difficult to achieve without compromising on functionality and features. If your site’s performance score is:

• Poor (0 – 49): we recommend taking some or all of the above steps to improve it.
• Needs improvement (50 – 89): you may want to take some actions to increase the score, or you may decide that your site’s performance is adequate for its purpose.
• Excellent (90 – 100): sit back and relax — your site is doing great!