Google's Core Web Vitals and how they affect your site's rankings

The way Google decides which websites show up first has changed over the years. As well as the content, what matters today is the experience users have when they land on your page: whether it loads fast, responds instantly and doesn't jump around while they read. To measure this, Google uses Core Web Vitals.

Updated in 2026. When we published this article, Core Web Vitals were about to launch and one of them was FID. Since March 2024, FID is no longer used: it was replaced by INP, a more complete metric. We've updated the guide with the current metrics and thresholds.

What are Core Web Vitals?

They're a set of three metrics Google uses to assess the user experience (UX) of a page:

• LCP: how long the main content takes to load.
• INP: how quickly the page responds when you interact with it.
• CLS: how stable the layout is while it loads.

They started to count towards rankings in 2021, first on mobile and then on desktop. One important detail: Google doesn't measure them in a lab, but with real data from Chrome users who visited your website over the last 28 days.

How much do they matter for SEO? They're one signal among many. Useful, relevant content is still what matters most, but between two similar pages, the one with the better experience has the edge. And above all, a fast website converts better: fewer people leave before it loads.

The values Google expects

To pass, at least 75% of visits to your page need to fall into the "good" range:

Metric	Good	Needs improvement	Poor
LCP (loading)	up to 2.5 s	up to 4 s	over 4 s
INP (responsiveness)	up to 200 ms	up to 500 ms	over 500 ms
CLS (stability)	up to 0.1	up to 0.25	over 0.25

1. Loading, or LCP (Largest Contentful Paint)

LCP measures how long it takes for the largest element visible on screen to appear when you arrive: usually the hero image, a video or a prominent block of text.

For example, if you open a blog post and everything has loaded except the main photo, LCP isn't counted until that photo appears.

The elements that can count as LCP are:

• Images (<img>, including those inside an <svg>).
• The poster image of a <video>.
• Elements with a background image loaded with url().
• Blocks of text, such as paragraphs and headings.

How to improve it:

• Compress your images and use modern formats such as WebP or AVIF, at the exact size they're displayed.
• Don't delay the main image with lazy loading: that one should load first.
• Choose good hosting and, if you can, a CDN that serves the website from close to the user.
• Cut down the CSS and JavaScript that block loading, and any unnecessary fonts.

2. Interactivity, or INP (Interaction to Next Paint)

INP measures how long the page takes to react when you do something on it: press a button, open a menu, tick a box or type in a field.

Unlike the old FID, which only measured the first interaction, INP takes into account every interaction during the visit and keeps one of the slowest. In other words, it reflects much better what it really feels like to use the website.

For example, if on a booking website you press "Search flights" and nothing happens for a second, that wait is what INP penalizes.

How to improve it:

• Cut down on JavaScript: the less code the browser has to run, the sooner it can respond.
• Split heavy tasks into small chunks so they don't block the page.
• Review third-party scripts (chats, pixels, widgets) and remove the ones you don't use.
• On WordPress, be wary of themes and plugins that load a lot of code on every page.
• Give immediate visual feedback when something is pressed (a colour change, a loading indicator), even if the result takes a moment.

3. Visual stability, or CLS (Cumulative Layout Shift)

CLS measures how much the elements on the page move while it loads. It's surely happened to you: you're about to tap a link and, at that very moment, an image or an ad pops in above it and you end up tapping something else.

The more elements move, and the further they move, the worse the CLS.

How to improve it:

• Always specify the width and height of images and videos, so the browser reserves space for them before they load.
• Reserve space for ads, maps, embedded videos and cookie notices.
• Don't insert new content above what's already on screen, unless the user asks for it.
• Load fonts properly so the text doesn't change size when the final font appears.

And don't forget the content

Core Web Vitals help, but they're no substitute for the essentials: content that genuinely answers what the user is looking for. If a text is repetitive, vague or looks copied from another page, Google will consider it of little relevance, however fast it loads.

Some guidelines that still apply:

• Use keywords naturally, without cramming the text with the same phrase.
• Lean on synonyms and variations: they help Google understand the topic.
• Images, tables and infographics add a lot, as long as they're optimized.
• Review and update your old articles when the information changes.

How to measure your website's Core Web Vitals

• Google Search Console: in the left-hand menu, under Experience, open the Core Web Vitals report. You'll see which URLs are good, which need improvement and which are poor, on mobile and desktop.
• PageSpeed Insights (pagespeed.web.dev): enter any URL and it shows you real user data plus an analysis with specific recommendations.
• Lighthouse, in Chrome's developer tools, for testing while you work on the website.

Is your website failing Core Web Vitals? Tell us and we'll tell you what's slowing it down.