Key takeaways
- Core Web Vitals are three measurements of real visitors’ experience: loading (LCP), responsiveness (INP) and visual stability (CLS).
- Google’s good targets are LCP within 2.5 seconds, INP of 200 milliseconds or less, and CLS of 0.1 or less, measured at the 75th percentile of page loads on mobile and desktop.
- Google says it highly recommends good Core Web Vitals for success with Search, as part of a wider page experience. They support rankings alongside useful content.
- Check them for free in Search Console and PageSpeed Insights. Most fixes come down to lighter images, less third-party code and reserving space for anything that loads late.
What are Core Web Vitals?
Core Web Vitals are three measurements Google uses to describe how a page feels to real visitors. According to web.dev, Google’s site for web developers:
- Largest Contentful Paint (LCP) measures loading: how long it takes for the main content, usually the hero image or headline, to appear.
- Interaction to Next Paint (INP) measures responsiveness: how quickly the page reacts when someone taps, clicks or types.
- Cumulative Layout Shift (CLS) measures visual stability: how much the page jumps around while it loads.
INP became a stable Core Web Vital in 2024, replacing First Input Delay (FID) as the responsiveness measure.
The numbers to aim for
- LCP: 2.5 seconds or less.
- INP: 200 milliseconds or less.
- CLS: 0.1 or less.
Google measures these at the 75th percentile of page loads, separately for mobile and desktop. In plain terms, at least three out of four visits should hit each target. A page passes when it meets all three.
Do Core Web Vitals affect Google rankings?
Google’s Search documentation says it highly recommends that site owners achieve good Core Web Vitals for success with Search, and that they align with what its core ranking systems seek to reward, alongside other page experience signals. They are one part of a bigger picture. A fast page with thin content will not outrank a genuinely useful one. A slow, jumpy page makes every visitor’s experience worse, and that costs leads whether or not it costs rankings.
How to check your site
- Search Console: the Core Web Vitals report shows how groups of your pages perform for real visitors, split by mobile and desktop.
- PageSpeed Insights: enter any URL to see real-visitor data, where Google has enough of it, plus a lab test with suggestions.
- Chrome DevTools and Lighthouse: useful for developers testing fixes. Lighthouse cannot measure INP directly and uses Total Blocking Time as a stand-in.
Real-visitor data comes from the Chrome User Experience Report, so a new or low-traffic page may not have enough data yet.
What usually fixes each one
Slow LCP
- Compress and resize the hero image, and serve modern formats such as WebP or AVIF.
- Preload the hero image so the browser fetches it first.
- Cut slow server response times with good hosting and caching.
- Keep the main content out of sliders and heavy scripts.
Poor INP
- Remove third-party scripts you do not need: old tracking pixels, chat widgets, plugins.
- Load the scripts you keep after the main content.
- Break up long-running JavaScript so the page can respond between tasks.
High CLS
- Set width and height on images and videos so space is reserved.
- Reserve space for ads, banners and embeds that load late.
- Load web fonts in a way that does not reflow the page.
Why it matters for leads
Most local and B2B buyers first see your site on a phone, often from an ad or a search result. Every second of loading and every jump in the layout is a chance for them to leave before they reach your form or phone number. Paid traffic makes this costly: you pay for the click either way.
Where to get help
We build and fix websites with performance tracked from the start. See our website service, or read our guide to answer engine optimization for how fast, clear pages also help with AI search.