Core Web Vitals are a set of performance metrics that Google uses to measure user experience on your website. They directly influence your Google rankings, so understanding and improving them is essential for any business serious about SEO in 2026.
What Are Core Web Vitals?
Core Web Vitals consist of three key metrics. Largest Contentful Paint (LCP) measures how quickly the main content of your page loads — Google wants this under 2.5 seconds. Interaction to Next Paint (INP) measures how quickly your page responds to user interactions like clicks or taps — aim for under 200 milliseconds. Cumulative Layout Shift (CLS) measures visual stability — how much the page jumps around while loading. A score below 0.1 is considered good.
How to Check Your Core Web Vitals for Free
The easiest way to check is using Google Search Console. Log in, navigate to the ‘Experience’ section, and click ‘Core Web Vitals’. You’ll see a report showing which URLs on your site are passing, need improvement, or are failing. This uses real-world data from actual visitors — called ‘field data’.
Using PageSpeed Insights
Go to pagespeed.web.dev and enter your URL. You’ll get both lab data (simulated) and field data (real users) for each Core Web Vital. The tool also provides a prioritised list of opportunities to improve your scores, making it clear where to focus your efforts.
Using Chrome DevTools
If you’re more technically inclined, open Google Chrome, right-click on your website and select ‘Inspect’, then navigate to the ‘Performance’ tab. You can record a page load and see exactly where time is being spent and which elements are causing performance issues.
Common Issues and How to Fix Them
Poor LCP is usually caused by large, uncompressed images or slow server response times. Fix it by compressing images (use WebP format), enabling browser caching, and upgrading your hosting. Poor CLS is often caused by images without defined dimensions or ads that load after the page. Always specify width and height attributes on images. Poor INP is typically caused by heavy JavaScript execution. Minimise third-party scripts and defer non-critical JavaScript.
Why This Matters for Your Rankings
Since 2021, Google has used Core Web Vitals as a ranking factor under its ‘Page Experience’ update. A site with poor Core Web Vitals will rank lower than a comparable site with good scores, all else being equal. More importantly, a fast, stable site keeps visitors engaged and converts more of them into customers.