Summary: LCP, INP and CLS measure real user experience. Here's what each means and the fixes that improve them most.
Core Web Vitals measure how fast and stable your pages feel to real users. Improving them helps SEO and, more importantly, conversions.
The three metrics
| Metric | Measures | Good threshold |
|---|---|---|
| LCP (Largest Contentful Paint) | Loading speed of main content | ≤ 2.5 s |
| INP (Interaction to Next Paint) | Responsiveness to clicks and taps | ≤ 200 ms |
| CLS (Cumulative Layout Shift) | Visual stability | ≤ 0.1 |
Improving LCP
- Use modern image formats (WebP, AVIF) and correct sizing.
- Preload the hero image or font.
- Use fast hosting, server caching and a CDN.
- Reduce render-blocking CSS and JavaScript.
Improving INP
- Reduce heavy JavaScript and third-party scripts.
- Break up long tasks and defer non-essential code.
- Avoid large DOM sizes.
Improving CLS
- Set width and height on images and embeds.
- Reserve space for ads and dynamic content.
- Use
font-display: swapcarefully with matched fallback fonts.
Measure with field data
Use PageSpeed Insights and Search Console's Core Web Vitals report, which reflect real users, not only lab tests.
FAQs
Why is my mobile score low?
Mobile devices and networks are slower; heavy images and scripts hurt most there.
Do page builders slow sites?
They can. Lean themes, caching and careful plugin choice help.
Will a faster site rank higher?
Speed is one signal among many, but it consistently improves user experience and conversions.
