Core Web Vitals Explained: How to Improve LCP, INP and CLS
Core Web Vitals are Google's three measures of real-world page experience: how fast the main content loads, how quickly the page responds, and how stable the layout is.
The three metrics
| Metric | Measures | Good |
|---|---|---|
| LCP – Largest Contentful Paint | When the largest visible element renders | 2.5 s or less |
| INP – Interaction to Next Paint | How quickly the page responds to taps and clicks | 200 ms or less |
| CLS – Cumulative Layout Shift | How much content jumps around | 0.1 or less |
Run key pages through the Page Speed Checker to see where you stand.
How to improve LCP
- Compress and resize the hero image, and serve WebP or AVIF.
- Do not lazy-load the main above-the-fold image.
- Reduce server response time with caching and a CDN.
- Remove render-blocking CSS and scripts.
How to improve INP
- Break up long JavaScript tasks so the page stays responsive.
- Defer third-party scripts such as chat widgets and ad tags.
- Keep the DOM small and click handlers light.
How to improve CLS
- Set width and height on images and video.
- Reserve space for ads and embeds.
- Avoid inserting banners above existing content after load.
Do not forget mobile
Most visits come from phones, which are slower than desktops. Check them with the Mobile-Friendly Test, and see how oversized images hurt speed in our image SEO guide.
Frequently asked questions
What are good Core Web Vitals scores?
Google considers LCP of 2.5 seconds or less, INP of 200 milliseconds or less and CLS of 0.1 or less to be good, measured at the 75th percentile of real visits.
Do Core Web Vitals affect rankings?
They are part of Google's page experience signals, but relevance and content quality matter far more. Treat speed as a tie-breaker and a user-experience goal.
Why do lab and field results differ?
Lab tests simulate one device and network. Field data comes from real users on many devices, so it is usually the better guide.