Performance
Core Web Vitals 2026: Fix LCP, CLS & INP to Improve Google Rankings
Core Web Vitals are Google's three field metrics for user experience: Largest Contentful Paint, Cumulative Layout Shift and Interaction to Next Paint. They are measured from real Chrome users, not from a lab test.
They are a ranking signal, but a tie-breaker rather than a primary one. Their bigger effect is commercial: slow pages lose users before content quality ever matters.
Free tools used in this guide
What Are the Core Web Vitals Thresholds?
A URL passes only when the 75th percentile of real users is in the good band for all three metrics.
| Metric | Good | Needs improvement | Poor |
|---|---|---|---|
| LCP — loading | ≤ 2.5 s | 2.5 s – 4.0 s | > 4.0 s |
| CLS — visual stability | ≤ 0.1 | 0.1 – 0.25 | > 0.25 |
| INP — responsiveness | ≤ 200 ms | 200 ms – 500 ms | > 500 ms |
How Do You Fix Largest Contentful Paint?
- Identify the LCP element — usually the hero image or headline — and make it the highest-priority resource.
- Preload the hero image and set fetchpriority="high"; never lazy-load it.
- Serve images in AVIF or WebP at the displayed size, not the original size.
- Remove render-blocking CSS and JavaScript from the critical path.
- Cut server response time below 600 ms with caching or a CDN.
How Do You Fix Cumulative Layout Shift?
- Set explicit width and height (or aspect-ratio) on every image, video and iframe.
- Reserve space for ads, embeds and cookie banners instead of injecting them into flow.
- Load fonts with font-display: swap and a matched fallback metric to avoid reflow.
- Never insert content above existing content after load.
How Do You Fix Interaction to Next Paint?
- Break long JavaScript tasks into chunks and yield to the main thread.
- Remove or defer third-party scripts — tag managers are the most common INP offender.
- Debounce expensive input handlers and move heavy computation to a web worker.
- Avoid large hydration payloads on interactive pages; ship less JavaScript.
How Should You Measure Core Web Vitals?
Use field data for decisions and lab data for debugging. The Chrome User Experience Report and Search Console's Core Web Vitals report show real users; Lighthouse shows a simulated run that is useful for isolating a cause.
Always measure mobile first. Mobile field data is what Google evaluates for most sites.
Frequently Asked Questions
Are Core Web Vitals a ranking factor?
Yes, as part of the page experience signals. They rarely outweigh relevance and authority, but they act as a tie-breaker between comparable pages.
What replaced First Input Delay?
Interaction to Next Paint replaced FID in 2024. INP measures the latency of all interactions during a visit, not just the first one.
Why does Lighthouse disagree with Search Console?
Lighthouse is a single simulated lab run; Search Console reports the 75th percentile of real Chrome users over 28 days. Trust the field data for decisions.
How long until Core Web Vitals improvements show up?
Field data uses a rolling 28-day window, so expect roughly four weeks before Search Console reflects a fix.