Don’t miss your Core Web Vitals

Cathryn says: “Make sure that Core Web Vitals are not missed when you’re looking at other elements, such as content strategy.

User experience is becoming more important than ever, especially this year.”

Why are Core Web Vitals so important to user experience?

“Core Web Vitals are Google’s indication when there is a potential issue on your site, which will lead you to investigate user experience a bit more.

Things like the Largest Contentful Paint (LCP) and First Contentful Paint (FCP) measure the page load or rendering and make sure that it takes less than 2.5 seconds. It also looks at things like Cumulative Layout Shift (CLS), which monitors any movement on the page.

These Core Web Vitals show where there are URL issues, and they enable you to isolate the specific URLs where these occur. That will provide the framework for you to look at user experience on those particular URLs and what’s going on, using various different tools to do so.”

Largest Contentful Paint (LCP) is one of the 3 core metrics in Core Web Vitals, so how would you summarise that and what is the impact of it?

“This is one that developers often struggle to get working. Basically, it measures the time between when the website first loads and when the largest thing on that page renders – whether it’s an image, a video, or a large block of text. It’s a measure of how long it takes before a user will see the information that they need to see.

There are various ways that you can optimize that, like by preloading certain images. One of the tools that I use with developers is Google Lighthouse. That will give you some general tips on things to improve.

It will show you the LCP element (the ‘largest’ content element on the page), which will allow you to think about preloading that image or looking at other tools to minimise your JavaScript or CSS and try to fix any blocking resources that might be slowing this down.

It’s all about measuring the page load, really. You are trying to make sure that everything on the page loads within 2.5 seconds.”

If it’s a long page that goes beyond the bottom of the screen, do those elements count as well?

“Yes. It includes all the elements of the page, whether it’s long or short. You want to make sure that it all comes up very quickly for the user.

This aspect of user experience is about the page loading as fast as possible so that, as soon as they click on the URL, they get all the information that they expect to see.

That will prevent people from leaving the site and going back to search, which is why things like bounce rate are also important factors. You should not only be looking at your Core Web Vitals, but also your Google Analytics data around bounce rate, general engagement rates, and how much time people are spending on site or on certain pages

All of that will give you a feel as to whether there is a wider issue going on. Why is your LCP low? Why is it not what it needs to be?

Bounce rate is a metric that you have to take with a pinch of salt for various reasons. If the bounce rate is high, it could be because the page is taking too long to load, or because the content was not what they expected. It could be down to content as well as user experience. It could also be that they found what they were looking for straight away.

That’s why you should look at that in relation to other metrics such as the LCP, your engagement rate on that page, and where those drop-offs are happening. If you’re trying to get sales down the line or you’re looking to get more registrations, where is the drop-off? Bounce rate is just one of the metrics that need to be looked at, in context.

The bounce rate is an indicator that something may be wrong, but you have to research it and find out what the issue is. It’s not the problem, it’s the indicator. You’re using Core Web Vitals indicators and Google Analytics indicators to work out which URLs have issues, then looking at those through other user testing tools.

You can use things like Hotjar for screen recording, which will allow you to see how users are interacting with that page, and then potentially identify user experience issues to fix. Core Web Vitals and Google Analytics Data are a starting point in this whole process.”

The next main metric in Core Web Vitals is Interaction to Next Paint (INP), so what does that mean?

“That is looking at the general responsiveness of the page, and each interaction needs to be less than 200 milliseconds.

All these little metrics essentially come down to page speed and page load. There are various ways that Google is interpreting it, but it’s a measure of page responsiveness.

It’s about how long it takes for any interaction on the page to deliver what it intends to do. If you have video content, and your users are clicking on different links on the site, how long does it take for those elements to respond?

If the purpose of that page is to read through and then go to a call to action, is there responsiveness? Are people clicking around and moving around the page? How long does it take for the page to respond to those interactions? Looking at hotspots and that kind of data can help with that as well.”

What does the third core metric, Cumulative Layout Shift (CLS), measure?

“CLS basically measures the movement in the site, and whether there are any major jumps or even slight shifts. Sometimes it’s not obvious to the naked eye, but Google is measuring that.

If the code is not particularly well structured or things are not very smooth from a development point of view, then that can affect movement, and CLS is a measurement of how much the content on that page moves unexpectedly while the user is looking at it.

One example of this is when you load an article and start reading but then, after a few seconds, a huge advert appears and shifts the text all the way down the page. That’s not the greatest user experience, and it’s definitely something to avoid.”

Are these metrics likely to change or expand over the next couple of years?

“The challenge with these metrics at the moment is explaining them in a real sense. Even developers struggle to understand exactly what they’re trying to do here.

If there’s a way to do that, Google will hopefully make it a little bit easier to understand the metrics, what they actually mean, and what developers and SEOs can take action on.

However, I think potentially more metrics will come out of this as well. One thing that’s not obvious in the metrics right now is that they are fundamental to page speed, but they’re just breaking it down. There isn’t an overall page speed metric within this.”

Does your performance need to be at the highest standard or does it just need to be better than your competitors’?

“On the business side, if your competitors don’t generally have well-performing sites, from a competitive point of view, it wouldn’t affect you as much. However, these little metrics are really important for ranking now.

Improving this is going to help you in a number of ways. You’ll be better than your competitors, it should have an impact on ranking, and it will create a better experience for your customers. Hopefully, that means you will get more customers out of it.

If you can get your site in a much stronger position than your competitors, then it’s a win-win.”

Can you measure the financial or business impact of improving these scores?

“If it’s a sales generating site, you know what the sales are. If you get the conversion rate up on that particular page, then you quantify the impact of this by looking at the increase in sales, and try to sell it in that way.

A lot of people spend a lot of time trying to generate traffic to the site, but the whole user experience is sometimes forgotten about. If you work on trying to improve the conversion rate and your conversion rate optimization, you can try and quantify that for the business.

If they can get that up by 2%, you could estimate how many additional sales that could make – or, if it’s a lead generating site, then how many extra leads you can obtain if you get a better conversion rate.”

Could a conversion rate specialist own this activity instead of the SEO?

“If you’ve got a conversion rate optimization specialist, then this could definitely be their job. The SEO’s role in that would be bringing to their attention things like Core Web Vitals and the issues that you’re seeing in the URLs.

Running those other tools like Google Lighthouse and looking at all the different indicators can at least highlight the issues that you are having, because that will affect SEO performance. It’s a case of working closely with them but, if there are UX teams in bigger organisations, they are the ones that should be owning it.

However, it is important for SEOs to take responsibility for helping to improve those scores.”

How often should Core Web Vitals be checked and how much time should be spent on it?

“It doesn’t necessarily change vastly because it measures the whole site, but it would be something that you’d put into your monthly regular checks just to make sure that no URLs are coming up as poor.

Particularly on mobile, you see a lot of sites that have poor URLs, so it’s worth checking that regularly and running things like Lighthouse scores to make sure that they’re in a good position with high percentages.

It gets trickier when you work with smaller companies. Bigger companies have the resources and the time to do that. Smaller companies are where this gets missed. They spend quite a bit of time optimizing their content, which is the right thing to do, but they don’t look at the technical SEO elements, the user experience, and working with your in-house developers or the agency developers that you have.”

If an SEO is struggling for time, what should they stop doing right now so they can spend more time doing what you suggest in 2025?

“Stop producing too much content. Focus on quality content. With all the latest AI developments, particularly AI summaries, it’s important to have credible, quality content.

Take the time that you would have spent filling your monthly blog quota and put that into your technical SEO, Core Web Vitals, and looking at the user experience of your pages.”

Cathryn Stormont is a Freelance SEO Consultant, and you can find her over at Digifreelancer.co.uk.