Advanced seo 74da3a3
Cyrus Shepard





Video Transcription




What are Core Web Vitals?



It's not so much about the text of the page, which are traditional ranking signals, but more about the user experience and what it's like, how pleasant it is to use the page, how useful it is. These are especially important on mobile when sometimes the speed isn't as high. So that's what Google is measuring here. So that's what it is.

Where is this going to affect rankings? 



So that's an important point. So this could potentially affect a lot of ranking results. 

When is it going to happen? 

Well, Google has told us that it's going to happen sometime in 2021. Because of COVID-19, they have pushed back the release of this within the algorithm, and they want to give webmasters extra time to prepare.

They have promised us at least six months' notice to get ready. As of this recording, today we have not received that six-month notice. When that updates, we will update this post to let you know when that's going to be. So anytime Google announces a ranking factor change, the big question is: 

How big of a change is this going to be?

How much do I have to worry about these metrics, and how big of results are we going to see shift in Google SERPs? Well, it's important to keep in mind that Google has hundreds of ranking signals. So the impact of any one signal is usually not that great. That said, if your site is particularly poor at some of these metrics, it could make a difference.


The other thing to consider, some Google signals have outsized impact beyond their actual ranking factors. Things like page speed, it's probably a pretty small signal, but as users experience it, it can have outsized influence. Google's own studies show that for pages that meet these thresholds of Core Web Vitals, visitors are 24% less likely to abandon the site.


Three signals for Core Web Vitals

So I want to jump briefly into the specifics of Core Web Vitals, what they're measuring. I think people get a little hung up on these because they're very technical. Their eyes kind of glaze over when you talk about them. So my advice would be let's not get hung up on the actual specifics. But I think it is important to understand, in layman's terms, exactly what's being measured.


1. Largest contentful paint (LCP)

The first being largest contentful paint (LCP). This basically asks, in layman's terms, how fast does the page load? Very easy concept. So this is hugely influenced by the render time, the largest image, video, text in the viewport.



2. Cumulative layout shift (CLS)

The second thing, cumulative layout shift (CLS). Google is asking with this question, how fast is the page stable? Now I'm sure we've all had an experience where we've loaded a page on our mobile phone, we go to click a button, and at the last second it shifts and we hit something else or something in the page layout has an unexpected layout shift.

That's poor user experience. So that's what Google is measuring with cumulative layout shift. How fast is everything stable? The number one reason that things aren't stable is that image sizes often aren't defined. So if you have an image and it's 400 pixels wide and tall, those need to be defined in the HTML. There are other reasons as well, such as animations and things like that.

But that's what they're measuring, cumulative layout shift. 

3. First input delay (FID)


It's not a good experience when you click on something and nothing happens or it's very slow. So that's what that's measuring. That can depend on your JavaScript, third-party code, and there are different ways to dig in and fix those. So these three all together are Core Web Vitals and play into the page experience signals. So like I said, let's not get hung up on these.

How to measure & fix

Let's focus on what's really important. If you have a problem, how do you measure how you're doing with Core Web Vitals, and how do you fix those issues? Google has made it very, very simple to discover. The first thing you want to do is look in Search Console. They have a new report there — Core Web Vitals. They will tell you all your URLs that they have in their index, whether they're poor, needs improvement, or good.

If you have URLs that are poor or needs improvement, that's when you want to investigate and find out what's wrong and how you can improve those pages. Every report in Search Console links to a report in Page Speed Insights. This is probably the number-one tool you want to use to diagnose your problems with Core Web Vitals.

It's powered by Lighthouse, a suite of performance metric tools. You want to focus on the opportunities and diagnostics. Now I'm going to be honest with you. Some of these can get pretty technical. You may need a web developer who is an expert in page speed or someone else who can comfortably address these problems if you're not very technical.

We have a number of resources here on the Moz Blog dealing with page speed. We'll link to those in the comments below. But generally, you want to go through and you want to address each of these opportunities and diagnostics to improve your Core Web Vitals score and get these out of poor and needs improvement into good. Now if you don't have access to Search Console, Google has put these reports in many, many tools across the web.



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