Quick answer
Core Web Vitals are three Google metrics that measure real user experience: Largest Contentful Paint (loading), Interaction to Next Paint (responsiveness) and Cumulative Layout Shift (visual stability). Passing all three at the 75th percentile gives visitors a faster, steadier page.
Key takeaways
- LCP should be 2.5 seconds or less.
- INP should be 200 milliseconds or less.
- CLS should be 0.1 or less.
- Use real user data, not just lab tests.
What do the three metrics measure?
| Metric | Measures | Good score |
|---|---|---|
| LCP | How fast the main content appears | 2.5 seconds or less |
| INP | How quickly the page responds to taps and clicks | 200 ms or less |
| CLS | How much the layout jumps | 0.1 or less |
How do you fix a slow LCP?
- Compress images and serve modern formats such as WebP.
- Preload the main hero image.
- Reduce server response time.
- Remove render-blocking scripts and styles.
How do you improve INP?
INP replaced First Input Delay as a Core Web Vital in 2024. It looks at every interaction, not just the first.
Long JavaScript tasks are the usual cause. Break up heavy scripts, remove unused plugins and delay third-party tags that are not essential.
How do you stop layout shift?
- Set width and height on images and video.
- Reserve space for ads and embeds.
- Avoid inserting banners above content after load.
- Load fonts with a sensible fallback.
How do you check your scores?
Use PageSpeed Insights for field data from real visitors, and the Core Web Vitals report in Search Console to find groups of slow pages. Retest after each change. Passing Core Web Vitals will not rescue weak content, but it removes a reason for users to leave.
Quick wins to try first
- Compress and resize your biggest images.
- Remove plugins and scripts you no longer use.
- Add width and height to every image.
- Delay chat widgets and tracking tags until after the page loads.
- Use a content delivery network if visitors come from far away.
These changes are low risk and often improve all three scores at once.
Bottom line
Make the main content load quickly, respond instantly to taps and stay still while loading. Fix the worst pages first and recheck with real user data.
Sources and further reading
Checked against the sources above and our own project experience. Last reviewed 7 October 2026.
