Core Web Vitals: What They Are and How to Pass

By Sean McCoy2 November 20265 min read
Laptop and tablet showing a responsive website

Core web vitals are three measurements Google uses to judge how a page feels to real visitors: how fast the main content loads (LCP), how quickly the page responds when someone taps or clicks (INP), and how much the layout jumps around while it loads (CLS). A page passes when most real visits score "good" on all three. They're part of Google's page experience signals, so they matter for SEO, but helpful content still matters more.

What are core web vitals?

Google core web vitals are the three page experience metrics Google treats as most important. They're measured from real Chrome users visiting your site, not just a lab test.

MetricWhat it measuresGoodPoor
Largest Contentful Paint (LCP)How long the biggest image or block of text takes to appear2.5 seconds or lessOver 4 seconds
Interaction to Next Paint (INP)How quickly the page responds to taps, clicks and key presses200 milliseconds or lessOver 500 milliseconds
Cumulative Layout Shift (CLS)How much the content moves around unexpectedly while loading0.1 or lessOver 0.25

INP replaced an older metric, First Input Delay (FID), in March 2024. Google's own explanation is on web.dev.

Does core web vitals affect SEO?

Yes, but less than many people think. Core web vitals became part of Google's page experience signals in the 2021 core web vitals update. Google has said that good scores don't guarantee top rankings, and a slow page with the most useful answer can still outrank a fast page with a weak one.

So treat core web vitals SEO work as a tie breaker and a conversion booster, not a shortcut to page one. The bigger win is often for visitors: a fast, stable page keeps people on the site long enough to call or buy.

How do you check core web vitals?

Three free tools show your scores:

  • PageSpeed Insights. Enter a page address to see field data from real visitors (if Google has enough) and a lab test with suggestions.
  • Google Search Console. The Core Web Vitals report groups your pages into good, needs improvement and poor, for mobile and desktop. Our Google Search Console guide shows how to set it up.
  • Chrome DevTools (Lighthouse). Useful for testing changes before they go live, but it's a lab test on your own computer, not real visitors.

Small sites with little traffic may show "no data" for field results. In that case, use the lab scores as a guide.

What does "core web vitals assessment failed" mean?

When PageSpeed Insights says your core web vitals assessment failed, at least one of the three metrics isn't "good" for 75% of real visits over the past 28 days. The report shows which metric failed. Because the result is based on 28 days of real visits, fixes take a few weeks to show up as a pass.

How do you improve core web vitals?

Core web vitals optimisation starts with the metric that failed:

Improve LCP (loading)

  • Resize and compress images, and use modern formats like WebP
  • Don't lazy load the main image at the top of the page
  • Use good hosting and a content delivery network
  • Cut render blocking scripts and unused CSS

Improve INP (responsiveness)

  • Remove plugins, chat widgets and tracking scripts you don't need
  • Delay non-essential JavaScript until after the page loads
  • Break long scripts into smaller tasks

Improve CLS (layout shift)

  • Set a width and height on every image and video
  • Reserve space for banners, ads and embeds
  • Load web fonts so text doesn't jump when they arrive

What we see when regional businesses test their websites

When we run speed checks on small business websites in Mildura and across Sunraysia, the same few causes come up again and again. Photos are uploaded straight from a phone or camera at full size. Older WordPress sites carry plugins nobody uses any more. Sliders and background videos at the top of the home page slow the first view. Cookie banners and pop-ups push the content down after it has loaded.

Most of these are fixable without a rebuild. Where a site is old and the theme itself is the problem, a rebuild on a lighter setup can be cheaper than patching it. Our technical SEO service covers speed and core web vitals fixes, and our web design team builds new sites to pass from day one.

How do you pass the core web vitals assessment?

Fix the metric that failed, test the page again in PageSpeed Insights, then wait. Search Console has a "Validate fix" button in the Core Web Vitals report: click it once your fixes are live, and Google checks over the next 28 days. If a whole template (such as every blog post) fails, fix the template rather than each page.

Core web vitals are one part of technical SEO, alongside crawling, indexing, site structure and security.

Frequently asked questions

What is core web vitals in SEO?

In SEO, core web vitals are Google's three measures of page experience: loading speed (LCP), responsiveness (INP) and visual stability (CLS). They're one of many signals Google uses, alongside relevance, content quality and links.

Is core web vitals a ranking factor?

Yes, as part of Google's page experience signals, but the core web vitals ranking factor is a small one. Relevant, helpful content matters more. Good scores help most when pages are otherwise similar, and they help visitors stay on your site.

Why do my mobile and desktop scores differ?

Phones have slower processors and often slower connections, so mobile scores are usually lower. Google mainly uses the mobile version of your site for ranking, so focus on mobile first.

How long does it take to fix core web vitals?

Simple fixes like resizing images can be done in a day. Search Console's field data then takes up to 28 days to reflect the change, so allow about a month before expecting a pass.

Do I need a developer to fix core web vitals?

Not for every fix. Image resizing and removing unused plugins are often do-it-yourself jobs. Script changes, hosting moves and theme problems usually need a developer.

Want to know why your site is failing? Contact Rock Solid Marketing and we'll check your core web vitals and tell you what to fix first.

About Rock Solid Marketing

A marketing team that has helped businesses across Sunraysia and the Mallee since 2017, from our office on Deakin Avenue in Mildura.

Keep reading

All articles

Let’s Talk Marketing – Book Here

Let’s start by scheduling a free discovery call so we can get to know each other and see if we’re a good fit for your marketing needs.