Core Web Vitals are three specific measurements Google uses to judge how a real visitor experiences your website: how fast the main content loads, how quickly the page responds to a click or tap, and how much the layout shifts around while it loads. A good score does not guarantee a top ranking, but a poor one can hold your site back in search results, especially against competitors with faster pages.
The Three Metrics Explained
- Largest Contentful Paint (LCP): how long it takes for the biggest visible element (usually a hero image or heading) to load. Aim for under 2.5 seconds.
- Interaction to Next Paint (INP): how quickly your page responds after someone clicks a button or link. Aim for under 200 milliseconds.
- Cumulative Layout Shift (CLS): how much visible content jumps around as the page finishes loading, for example when an image loads late and pushes text down. Aim for a score under 0.1.
How to Check Your Core Web Vitals Score
You have two main options, and both are free.
- Open Google's PageSpeed Insights tool and enter your website's URL. It runs a live test and shows your LCP, INP, and CLS for both mobile and desktop.
- If your site is already verified in Google Search Console, open the Core Web Vitals report under the Experience section in the left-hand menu. This shows real visitor data collected over the past 28 days, grouped into "Good," "Needs improvement," and "Poor."
PageSpeed Insights tests a single page at a time and gives you a lab score. Search Console's report reflects actual visitors on your live site, so the two numbers can differ. The Search Console data matters more for your actual ranking, since it comes from real traffic.
How to Improve Each Metric
Improving LCP (Loading Speed)
- Compress and resize images before uploading them, and use modern image formats where your platform supports them.
- Turn on browser caching and, if your hosting plan supports it, page-level caching.
- Avoid loading large videos or unnecessary scripts above the fold.
Improving INP (Responsiveness)
- Remove or defer plugins and third-party scripts (chat widgets, tracking pixels) you don't actually need.
- Keep your CMS, theme, and plugins updated. Outdated code is often the biggest source of slow interactions.
Improving CLS (Visual Stability)
- Always set a width and height on images and embedded videos so the browser reserves space for them before they finish loading.
- Avoid inserting ads, banners, or pop-ups above existing content after the page has already loaded.
If your website runs on WordPress, a caching plugin combined with image optimization usually resolves most Core Web Vitals warnings without touching any code. For deeper speed fixes, see How to Speed Up a Slow-Loading Website.