What Are Google’s Core Web Vitals? User Experience and SEO

core web vitals

It is well known that Google rewards websites that are both helpful and easily accessible, and we are all aware that factors like site speed, responsiveness, and reliable content all factor into Google’s assessment of a site’s user friendliness, which in turn affects ranking.

But how in the world do we measure everything? There are tools to help, such as Lighthouse, Chrome DevTools, PageSpeed Insights, and the Google-developed Speed Report for Search Console, but with so many of them, it can be difficult to keep up.

Thankfully, Google understands this and launched Web Vitals at the beginning of the month. An endeavour to provide unified guidelines for quality signals that are crucial to producing a great user experience on the web, assisting business owners, marketers, or developers to quantify the experience of a site and find areas for improvement.

The Web Vitals programme, according to Google, “aims to simplify the landscape and support sites in focusing on the Core Web Vitals, the metrics that matter most.”

What are the Core Web Vitals?

Core Web Vitals are a subset of Web Vitals and are applicable to all pages. Each of the Core Web Vitals, which will be surfaced across all Google products, represents a different aspect of the user experience.

The current set concentrates on loading, interactivity, and visual stability as three facets of the user experience. Although Google has stated that the metrics that make up the Core Web Vitals will vary over time, these measures are not new, and there has never been any prior guidance, but what we do have now are the ideal ranges to target.

  • When the largest content element in the viewport becomes visible, it is measured by the Largest Contentful Paint (LCP). LCP must occur within 2.5 seconds of the page’s initial load in order for the user experience to be satisfactory.
  • First Input Delay (FID) measures a user’s initial perception of a website’s responsiveness and interaction. It gauges the amount of time between a user’s initial interaction with a page and the point at which the browser can actually react to that interaction. Pages with a FID under 100 ms ought to provide a smooth user experience.
  • Cumulative Layout Shift (CLS) measures both the distance the elements were moved and the amount of viewable content that was visible in the viewport. Pages should keep in mind the following to create a pleasant user experience:

How do I measure Core Web Vitals?

Use Chrome User Experience Report

Google presently recommends Chrome User Experience Report to capture information for each Core Web Vital in order to provide a quick summary and evaluation of site performance. In contrast to PageSpeed Insights and Search Console’s Speed Report, Chrome User Experience Report includes metrics for loading (LCP), interaction (FID), and visual stability (CLS), while Google promises the ability to assess it across the board is soon to come.

However, by employing this technique, you will be omitting specific, per-pageview telemetry, which is frequently required to precisely identify, monitor, and respond to relapses.

Measure Core Web Vitals in JavaScript

A simple wrapper for underlying web APIs that measures each statistic in a manner that precisely matches how it is reported by the Google tools mentioned above is included in the web-vitals JavaScript package.

Google claims it’s the simplest approach, but someone who isn’t familiar with code might find it intimidating.

Use the Web Vitals Chrome Extension

Unfortunately, it’s not as easy as just going to the Chrome extension page; you do need to do some research, although the 5-step installation instructions are rather simple. If you cringe at the notion of working with JavaScript and APIs, try this approach.

It enables you to examine not only the performance of your own sites but also those of your rivals and the entire internet.

Recommendations for improving your scores

The next stage is to optimise after measuring the Core Web Vitals and determining where improvements may be made. The instructions below provide detailed advice on how to tailor your pages for each of the Core Web Vitals:

Optimize LCP

Optimize FID

Optimize CLS

However, we’ve whittled it down for you.

Optimise LCP:

  • If your HTML is static and doesn’t need to update for every request, cache the assets.
  • Install a service-worker to serve HTML pages out of the cache in the browser’s background.
  • When you minify CSS, you can cut down on characters like spacing, indentation, and comments.
  • Image enhancement and compression for newer formats (JPEG 2000, WebP).

Optimise FID:

  • If at all possible, postpone using JavaScript.
  • Break up “long tasks” (long-running code) and stay away from JavaScript bloat.
  • Think about running JavaScript on a background thread using a web worker.

Optimise CLS:

  • When creating photos and videos, make sure to always include the width and height size properties.
  • If you want to display adverts, set aside space for the slot in advance.
  • The same goes for dynamic content; reserve enough room in the viewport so that when it loads, the page’s content doesn’t unexpectedly move about.

Because you’ll already have a strong basis to build upon as the score metrics change, we advise acting on Google’s recommendations as soon as possible.

Changes to all Web Vitals will be transparently described in this public CHANGELOG, according to Google.

You can learn more about Google’s web.dev platform here, as well as about our technical SEO services and more of our SEO offerings.