Google PageSpeed grade does not improve

In most cases, WP Rocket will improve your PageSpeed grade. The extent to which it improves depends on the baseline performance of your site: the hosting, plugins you’re using, content you’ve added, etc.

How can I improve Core Web Vitals?

Please see our guides:

Find your site’s baseline performance

Disable WP Rocket and run a PageSpeed test to see what your baseline scores are.

Alternatively, you can also run a test bypassing WP Rocket, by adding ?nowprocket to the URL, to find the baseline.

Then, reactivate WP Rocket and adjust the options as described below.

How WP Rocket can improve your score

Here are the specific WP Rocket features that will help improve the score:

Page caching

Caching is enabled automatically (unless your webhost is handling it) and will increase the overall score and Core Web Vitals. It also directly improves server response time.

Mobile caching

This option is enabled by default. It ensures your mobile site is cached, and all optimizations are applied there.

Delay JavaScript Execution

This is a very powerful feature which can help improve the following recommendations:

Learn more about this feature: Delay JavaScript Execution

Remove Unused CSS

Helps with Reduce Unused CSS
Reduces HTTP requests and overall page size

Load CSS Asynchronsously

Helps with CSS files of the Eliminate render-blocking resources
Helps with Preload Key Requests, for CSS files.

Load JavaScript Deferred

Helps with JavaScript files in the Eliminate render-blocking resources

LazyLoad for images

Helps with Defer Offscreen images

Preload Fonts

Helps with Preload Key Requests, for fonts hosted on your site
Google Fonts are automatically optimized

Add Missing image dimensions

May help with Cumulative Layout Shift

Minify CSS files

Helps with Minify CSS
Helps with Ensure text remains visible during webfont load

Minify JavaScript files

Helps with Minify JavaScript

Prefetch DNS requests

Helps with Preconnect to required origins

GZIP compression

This is applied automatically on Apache servers.
Helps with Enable text compression

Browser caching

This is applied automatically on Apache and LiteSpeed servers
Helps with Serve assets with an efficient cache policy

Check how if your score has improved

After activating and configuring the above options, run another PageSpeed test to see how it’s improved. Consult the detailed guides provided above to find out more.

Diagnostics are still present

After the optimizations are applied, some diagnostics may still present on the PageSpeed report.

However, for those cases, these diagnostics should have a much lower impact .

The impact of the diagnostics can also be seen by checking their icons. If everything went fine, the icons of the diagnostics will change from red triangles to yellow squares.

It's also important to reduce the usage of exclusions used across the optimizations. It's recommended to use exclusions only for major issues.

How to optimize further

There will likely be some remaining recommendations, which cannot be improved with WP Rocket. We’ve covered the most common ones in the list below:

All of our guides on PageSpeed recommendations can be found here.

Why is my mobile score is much worse than desktop?

Please see our guide: How to improve your mobile PageSpeed score.

How long does it take to see the improvements?

WP Rocket's speed improvements take place immediately. The report should change in real time, after you've enabled/disabled the optimization features.

However, the Load CSS Asynchronously and Remove Unused CSS features will show a notice to let you know you when they've been completed and are successfully applied to your site.

My score isn’t high enough, can you optimize my site for me?

We don’t provide an optimization service, but our support is here to help if there are specific issues using our features. Optimization is a complex task that will require some work on your part, too. In some cases, you may need the help of a developer. In that case, we recommend Codeable.

Regardless of the score, WP Rocket makes the actual loading time of your page faster, improving the experience for your visitors. To get another perspective of the speed, you could use a tool like Pingdom to measure the load time.

Core Web Vitals Assessment: Failed

The Core Web Vitals Assessment is the score based on the information taken from real visitors and collected during the last 28 days.

WP Rocket can't change the Core Web Vitals Assessment score. WP Rocket can have an impact specifically on the Diagnose performance issues metrics section.

However, in theory, with good results in the Performance metrics, the assessment could be improved with the time, as visitors will have the chance to interact with an optimized site.

GTmetrix grade does not improve

GTmetrix report is powered by Lighthouse, therefore, in most cases, addressing the recommendations in the PageSpeed report as explained above will improve GTmetrix results too.

Accessibility, Best Practices and SEO sections

lighthouse sections

WP Rocket's optimizations are aimed to address only audits from the Performance section of the PageSpeed report.

Audits and scores in the Accessibility, Best Practices and SEO sections are outside WP Rocket's scope, and should be addressed as instructed in Lighthouse official documentation:

WP Rocket errors caused on Mobile Friendly audits

In some cases, WP Rocket could trigger these Mobile Friendly audits in the SEO section of the PageSpeed report:

Document doesn't use legible font sizes
Tap targets are not sized appropriately

Firstly, to confirm WP Rocket is involved, you should check the test results with the ?nowprocket query string added to the affected URL. This will bypass WP Rocket's optimizations.

You can conclude WP Rocket is causing the problems when they don't appear in the ?nowprocket report. In those cases, you'd need to find which is the problematic feature as per this basic troubleshooting guide.