What are Core Web Vitals and how do they affect SEO?

Core Web Vitals, or CWV, are a set of metrics developed by Google to assess the user experience of a website’s pages.

They focus on aspects such as loading speed, interactivity, and visual stability – all of which can significantly impact your site’s search engine optimization (SEO).

Why are Core Web Vitals (CWV) important for SEO?

It is in Google’s best interest to provide its users with the best possible experience. Showing websites with poor Core Web Vitals at the top of search results would go against that goal.

Imagine clicking on a link and waiting five seconds before anything even begins to load. Frustration builds quickly, and chances are you won’t wait — instead, you’ll hit back and look for a better option.

This type of behavioral data is something Google analyzes continuously, and in the end, it can have a major impact on how well a site performs in organic search results.

Where can you check the status of Core Web Vitals?

One of the most effective and, above all, most cost-efficient ways to get a clear overview of a site’s Core Web Vitals is to use Google Search Console.

In the left-hand menu, you can choose to review “Core Web Vitals,” or “Viktiga webbvärden,” depending on whether your language settings are in English or Swedish.

It is also possible to use the free tool Google PageSpeed Insights to review the status of specific pages.

Here, you can also access much deeper insights into the relevant metrics.

Note that there is data for both desktop and mobile, and in some cases, a page may pass one test but not the other.

Which metrics are included in Core Web Vitals?

At present, Core Web Vitals include the following metrics:

• Largest Contentful Paint (LCP)
• Interaction to Next Paint (INP)
• Cumulative Layout Shift (CLS)

Below you’ll find explanations for each of these metrics and how to optimize them.

What is Largest Contentful Paint (LCP)?

LCP, or Largest Contentful Paint, measures how quickly the largest visible element on a webpage loads. This is often a large image or a headline. In practice, it shows how long it takes before the user sees that the main content of the page has been rendered.

Google uses LCP as part of its assessment of user experience. If loading is fast, visitors can view the most important content without delay, creating a positive experience. If LCP is slow, the page may feel sluggish, and users are more likely to leave.

According to Google’s guidelines, LCP should ideally occur within 2.5 seconds of the page starting to load.

How to optimize Largest Contentful Paint (LCP)

Improving LCP comes down to speeding up the loading of key content.

This might include optimizing images, reducing heavy scripts, and reviewing your web hosting performance. For example, you can compress images without sacrificing quality, load heavier elements only when needed (lazy loading), or choose a hosting provider with faster servers.

A fast-loading page not only improves user experience but also signals to Google that your site delivers high quality in this area.

Learn more about how to optimize LCP.

What is Interaction to Next Paint (INP)?

INP, or Interaction to Next Paint, measures how quickly a webpage responds to user interactions such as clicks or keyboard input.

Unlike the older metric FID (First Input Delay), INP tracks the entire visit rather than just the first interaction. This makes it a more comprehensive indicator of how responsive a site actually is during real use.

If a page feels sluggish when clicking around or filling out forms, it may be due to a high INP value. Google recommends keeping this value under 200 milliseconds for the site to feel fast and responsive.

How to optimize Interaction to Next Paint (INP)

To improve INP, you need to ensure that the page reacts quickly to user actions.

This often involves simplifying the underlying technology of the site, for example by reducing the amount of code being loaded, or by avoiding multiple processes running in the background simultaneously.

A low INP creates a smoother and more pleasant experience, which is appreciated by both visitors and search engines.

Read more about how to optimize INP.

What is Cumulative Layout Shift (CLS)?

CLS, or Cumulative Layout Shift, measures how much the content on a webpage shifts while the page is loading.

For example, it could be an image, button, or text that unexpectedly jumps down or to the side when another element loads. These movements can frustrate visitors and sometimes cause them to click the wrong thing, leading to a poor user experience.

Google uses CLS as part of its evaluation of a page’s user-friendliness. The less movement during loading, the better. A low CLS value indicates that the page is stable and pleasant to use, while a high value signals that the content shifts around in a way that can disturb users.

How to optimize Cumulative Layout Shift (CLS)

To avoid problems with CLS, all images, ads, and other page elements should have defined dimensions in the code before they are loaded, meaning a dedicated space is reserved on the page.

This prevents the layout from changing unexpectedly as content loads. It is an important part of creating a fast, stable, and user-friendly website.

Such an experience is not only appreciated by visitors but can also influence how well the site performs in Google’s search results.

Read more about how to optimize CLS.

In conclusion – don’t focus too narrowly on the results

At its core, it is of course an advantage to optimize your site as much as possible. At the same time, there is often more to lose from poor performance than there is to gain from achieving absolute perfection. A site whose pages load instantly, respond immediately, and don’t shift a single pixel during loading is certainly ideal, but rarely necessary.

What really matters is that the site meets the benchmarks that Google considers acceptable — ideally with some margin. Striving for complete perfection is rarely worth the effort, especially if it requires significant costs in time and/or money.

It’s not very likely that your site will climb in the search rankings just because it loads one percent faster when it’s already performing well. However, poor optimization can negatively affect organic visibility or prevent the site from reaching its full potential.