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The success of your website hinges on a little more than just looks; without a positive user experience in a practical sense, your website could be a huge turn off to consumers before it’s had a chance to wow with visuals. This user experience is the driver behind Google’s Core Web Vitals, a set of metrics used to measure the overall real-world useability of a site. 

In this article, we’ll be looking at what Google’s Core Web Vitals are, why they’re important, and how to optimise your site accordingly. 

What are Google's Core Web Vitals?

Created initially for web developers, Google’s Core Web Vitals are now metrics that can be used by any site owner to see how easy their site is to access and use.

The Core Web Vitals cover three main areas of useability on a site, which include page loading performance, the visual stability of a page (from the user’s perspective), and ease of interaction. 

A site with high scores in all these areas has a good chance of being rewarded on the SERPs, providing the rest of its SEO is up to scratch. 

How do Google report on page experience?

Within Google Search Console, a must-have tool for anyone interested in how their website is performing, there’s the option to dig into your page experience stats - think of it as a Core Web Vitals checker. This Page Experience report helps you better identify opportunities for improvement, and Core Web Vitalsforms a vital part of this report. 

What are the Core Web Vital metrics?

In technical terms, there are three main vitals that matter here - and a good score on all three is the key to improved rankings, not just one! Allow us to introduce you:

Largest Contentful Paint (LCP)

Does a slow loading page frustrate you when you’re browsing the web? You’re not alone there, and that’s what LCP metric measures: how long it takes for the page to show the user the largest block of content on the screen before the‘fold’, which is what you see before you have to scroll. You’re aiming for 2.5seconds or less - beyond that, and the risk of losing the user is much greater. 

A fast loading page pleases a user, as they're getting what they’re looking for quickly, and it pleases Google too - pages with fast load speeds tend to rankhigher.  

First Input Delay (FID)

Websites aren’t just to be looked at - they’re to be engaged with too. First Input Delay measures the time it takes for a part of the website to respond to a user’s input, such as clicks. 

Of course, external factors such as internet speed can play a part in this, but making sure your site is responsive to a user’s input puts your site in the best position of scoring highly here. The target is under 100 milliseconds!

It’s worth noting that FID isset to be replaced by INP (Interaction to Next Paint) in March 2024, upgrading to using an Event Timing API to generate even more accurate data relating to a user’s interaction with a site.  

Cumulative Layout Shift (CLS)

Small frustrations with your web page can cost you sales and enquiries. For example:you open a web page and see the Call To Action button you know you need.However, in the time it takes for your cursor (or thumb) to reach that button,the page loads fully and the content shifts, leaving you clicking nothing, or,worse, clicking something you weren’t aiming for, taking you to a page you didn’t need. Talk about annoying! 

Cumulative Layout Shift measures this on your web page, alerting you to moving content that could be causing frustration to your users, from shifting buttons like we’ve mentioned, to text that jumps around as the page loads and disturbs auser’s reading of it. 

Think of CLS as page stability - ideally, you want everything to load quickly and stay where it is! 

What else is considered a Core Web Vital? 

Here are a few other elements to consider when you’re getting your website up to full health; they’re all considered important by Google as part of their Core Web Vitals: 

Mobile friendliness 

It’s been estimated that mobile internet traffic accounts for 60% of total web traffic;if that’s not a reason to build a mobile-friendly website then we don’t know what is! Google knows this too and will actually ignore websites that are desktop-only. 

A website that is responsive to different screen sizes, adapting to fit each one, is best practice in web design and build these days, covering all bases for good user experience on different devices.  

Safe browsing

When you’re browsing the web,you expect, at the very least, that the pages you land on don’t contain malware or deceptive content, which can lead to all sorts of problems. It maybe goes without saying that at the first sniff of anything that isn’t as safe as it should be for the user, Google marks you down significantly.


The presence of an SSL certificate, indicated by ‘https’ and a lock symbol before a web address, authenticates a website’s identity and enables encryption, which means sensitive data can’t be stolen when a user inputs it on that URL.

No intrusive interstitials

As obvious as they may seem as a way of promoting an element of your business,such as a sale, pop-ups can disturb the browsing experience somewhat, and this is what’s meant by an intrusive interstitial. This goes for overlays on a website of any kind that obscure the main content on the page. 

Google much prefers interstitials that don’t disrupt the content, such as banners, or at the very least, ones that only partially cover content, and can be exited easily. 

Why are Core Web Vitals important?

As with most of the things that you should implement on your website, the benefits of paying attention to your Core Web Vitals are two fold. Firstly, you’re making your user’s experience a positive one, fostering trust as well as making the journey to making a purchase or an enquiry a simple one. 

Then, of course, a positive user experience gets a big thumbs up from Google, and they will prioritise a site that gives users what they need quickly. 

Do Core Web Vitals affect SEO?

Yes- Core Web Vitals are a ranking factor, as it all relates to the user experience. As we know, SEO is now geared towards the overall experience of the user (as it should be), and the way that a page performs can make or break that before they’ve even got to other ranking factors, such as the content on yoursite. 

How can I optimise my core web vitals?

If you’re wondering how to improve the Core Web Vitals on your site, the good news is that it IS possible. However, it’s best not to work blind on this; find out how your website is performing by obtaining a Core Web Vitals report, essentially doing a Core Web Vitals test yourself. Here you’ll see current performance rated Poor, Needs Improvement, or Good. 

There are several Core Web Vital checkers out there, but we’d always recommend you do this through Google’s very own Search Console, a fantastic resource for web performance reporting in general. 

From here, you’ll be able to identify the areas in which your site needs work, and head to your developers to get the ball rolling. If you’re technically minded,you may well find the following list (which is in no way exhaustive) of actions you may need to take to improve your Core Web Vitals helpful: 

Optimise and compress your images 

Big images mean big loading times, pushing that LCP score up. Compressing the file size won’t impact the size of the image on your site, or the quality in most cases, but it will impact your load times in a positive way, working to improve your Core Web Vitals. 

Get your images Lazy Loading 

Lazy loading means that your images only load as the user scrolls to where they are.This means that the page loading time isn’t impacted by all images, including the ones that can’t even be seen yet, loading at once.  

Defer the loading of JavaScript

Like Lazy Loading, JavaScript on your pages will, following implementation, only load once a user arrives at it, reducing the time taken to load the page initially. 

Optimise your fonts 

Who knew this would affect your page? Well, some fonts will slow down the loadspeeds on your web pages, as they require the browser to download them first. To combat this, we’d recommend using global fonts, which are easily recognised by browsers. 

Upgrade your hosting 

The server your site is hosted on will determine your load speeds to a certain extent. Therefore, although you might be making a saving by paying less for your hosting, you might be costing yourself in other areas - such as sales! Look into the performance of your hosting and invest if it’s impacting your Core Web Vitals.

How can 427 Marketing help you?

Will years of experience in digital marketing, we can help you optimise your site using the latest best practices from Google. We prioritise high quality SEO build around great, user orientated content that helps your users. If you wish to find out more, simply get in touch with us today and a member of the team will be on hand to help you.

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About Chris Simmons

Chris is our onpage SEO Specialist at 427 Marketing, having joined the team in early 2023. He works with our content team to cover the 4 pillars of SEO; content, onpage SEO, technical SEO and offpage SEO. Prior to joining the 427 Marketing team, Chris spent almost 10 years applying his SEO and content skills across several different industries in marketing agency and inhouse roles including tool hire, auctioneering, health care within the NHS and high end luxury retail in both B2B and B2C capacities. His passion for writing, content, UX, technical and on page SEO has expanded our content offerings, helping provide reliable advice about all things SEO to 427 Marketing.

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