Core Web Vitals are Google's three measures of how fast and stable your website feels to a real visitor. They affect both your search ranking and whether people stick around long enough to convert. Here's what they are, in plain English, and how to pass them.
The three metrics
Google grades every page on three things:
| Metric | What it measures | Good score |
|---|---|---|
| LCP — Largest Contentful Paint | How fast the main content loads | Under 2.5s |
| INP — Interaction to Next Paint | How quickly the page responds to taps | Under 200ms |
| CLS — Cumulative Layout Shift | How much the layout jumps as it loads | Under 0.1 |
Why they matter
Two reasons. First, Core Web Vitals are a confirmed Google ranking factor — faster, more stable pages get an edge. Second, they're a conversion factor: every extra second of load time loses visitors, and a layout that jumps around makes people mis-tap and leave.
How to improve them
- Compress and right-size images, and serve modern formats like WebP.
- Lazy-load images and video below the fold.
- Cut or defer heavy third-party scripts and unused plugins.
- Reserve space for images and embeds so nothing shifts — the main fix for CLS.
- Use fast, modern hosting and a CDN.
- Ship less JavaScript — the biggest lever for INP.
Platform makes a big difference
How easily you pass depends a lot on your platform. Custom-coded sites pass most easily because they ship only the code they need; plugin-heavy WordPress and some builders struggle without careful optimization. See the platform comparison, or how custom code is built for performance.
How to check your scores
Run your URL through Google's PageSpeed Insights, or open the Core Web Vitals report in Google Search Console. Both show your real-world scores and the specific fixes that will move them most.