Now, websites that offer a better user experience tend to rank higher than those that don’t. But how does Google know that users have a good experience on one website and a bad experience on another? What does it use to measure user experience?

What Are Google’s Core Web Vitals?

Just like humans have vital signs that provide signals to doctors about a patient’s well-being, so do websites. These Core Web Vitals are signals to Google that a website is offering a good user experience (or not). As of May 2021, these Core Web Vitals an official part of Google’s ranking factors, so it’s important for webmasters to pay attention to them.

These Core Web Vitals are:

• Cumulative layout shift (CLS)
• First input delay (FID)
• Largest contentful paint (LCP)

What Is Cumulative Layout Shift (CLS)?

Cumulative layout shift (CLS) occurs when content on a webpage shifts position. It happens when the content of a webpage isn’t loading in a synchronized manner. CLS can also occur when new content is loaded on top of existing content. It’s annoying to users because they may lose their place while reading your content or because a link they were about to click on has moved.

What Is First Input Delay (FID)?

First Input Delay (FID), is a measure of how quickly your website responds to an action from a user. For example, if a user clicks on a link, FID measures how long it takes to load the page that link leads to. A good FID score is 100 milliseconds or fewer. If a web page takes a long time to process a user’s action, that user may leave the website.

What Is Largest Contentful Paint (LCP)?

Largest Contentful Paint (LCP) is a metric that measures how long it takes for a webpage to load the largest object on the page. This largest object could be an image, a video, or a block of text. If this object takes a long time to load, a user can’t start enjoying the content on the page and may therefore click away.

What Other Vital Signals Does Google Use to Measure UX?

These three core vital signs aren’t the only signals Google looks for when it comes to measuring user experience. Google also looks for:

• Mobile-friendliness
• Safe browsing (no malware)
• HTTPS (not HTTP)
• Lack of pop-ups

Google also measures your click-through and bounce rates. If there’s something not in either list above that affects user experience negatively, users will click off your site, increasing your bounce rate, which in turn negatively affects your SERP rankings. 

Think of your own experiences as a user on the Internet. Try to emulate websites that you liked, on which you easily found what you were looking for and where the content was informative. Try to avoid features that you found annoying or that made you want to click away.