Even though website speed itself has not been an official ranking factor in Google’s SEO algorithm until now, experts have largely proclaimed its importance for good SEO. With the upcoming Core Web Vitals update planned by Google for May 2021, which adds 3 new metrics to the Page Experience signal, website speed officially becomes a ranking factor. So now many webmasters wonder what the immediate impact of that change will be on the SEO searches.

Website speed effect on organic searches after the Core Web Vitals update

The optimal website loading speed

It’s good to know that major shifts are not foreseen as a result of the new Google update, but still, if your site is not really well optimized, or if you are not sure where it stands, you are still bearing risk and Google is sending you a message to get to work. A good start for this is to figure out how your website currently scores on the 3 new metrics – Largest Contentful paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS) and what to aim for.

Useful website speed test tools

There are a lot of website speed test tools, which you can use to check your page loading times. Some of the most common ones are LighthousePageSpeed InsightsSearch Console > Core Web Vitals report, and more.

Website Speed Optimization Suggestions

Here’s a concise list of simple ways to optimize performance.

Lower Largest Contentful Paint (LCP) under 2.5s 

1.Optimize your images

The most common problem for website performance and LCP, in particular, are the large images that need to be loaded simultaneously and slow down the page. That is why you should consider the following optimizations:

  • Add lazy loading of images – that way not all images will be loaded at the same time upon opening the page. 
  • Use caching for static assets 
  • Serve an alternative image format – WebP. This is a very useful way to reduce the size of the images on your site. 

2.Minify your CSS and JavaScript

One of the easiest ways for big performance wins, in this case, is to use compression like Brotli or Gzip. Another possibility is to use plugins for WordPress sites. 

3.Limit 3rd party scripts

The more scripts that need to be loaded on the page, the slower it will open. Third-party scripts are for example tracking software, advertising scripts, heatmaps, and others. Once they serve their purpose, make sure you removed them so they don’t pile up slowing the website.

4.Get a faster web host

Having a fast server helps a lot for boosting the LCP metric. So if you have done all of the above and your site is still loading slow, see what’s happening with your hosting and how your provider can help optimize the environment for more performance.


Since website speed tests are greatly affected by the speed of the Internet connection, where sites with international traffic are most hurt, experts suggest that you use CDN. In case you wonder which of all those optimization suggestions should be the first on your list, take a listen to the users’ opinion.

Get First Input Delay (FID) under 100 milliseconds 

If you score poorly on this one, it is most likely that your JavaScript is the culprit. Minify and defer JavaScript to fix the issue. WordPress sites, that could be done with a click of the mouse from the plugin. 

Get Cumulative Layout Shift (CLS) under 0.1 

The CLS is largely a web design issue. The most common reasons for it are:

  • Images without dimensions  
  • Ads, embeds, and iframes with dimensions  
  • Dynamically injected content 
  • Custom Web fonts – AJ suggests using “swap” in CSS and instruct the browser to show the browser font first until the custom font gets loaded to avoid users seeing blanks on the page.
  • Actions waiting for a network response before updating the DOM 
  • Infinite scrolling 

In this blog, we focused entirely on optimizing website speed for the 3 new metrics that will become ranking factors in Google’s algorithm. But your optimization efforts should not stop with LCP, FID, and CLS. There are other things you can do that will improve your performance overall and have a positive impact not only on your SEO but on your user experience and business results.