Core Web Vitals in 2026: How to Pass LCP, INP and CLS
By Quadrex Labs · Updated
Quick answer
Core Web Vitals are Google's user-experience metrics: Largest Contentful Paint (LCP) should be under 2.5 seconds, Interaction to Next Paint (INP) under 200 milliseconds, and Cumulative Layout Shift (CLS) under 0.1. Most failures come from hidden or late-loading hero content, heavy JavaScript and images without reserved space.
The thresholds
| Metric | Measures | Good | Poor |
|---|---|---|---|
| LCP | Loading: when the main content appears | ≤ 2.5 s | > 4.0 s |
| INP | Responsiveness to taps and clicks | ≤ 200 ms | > 500 ms |
| CLS | Visual stability | ≤ 0.1 | > 0.25 |
Fixing LCP
- +Preload the hero image and give it high fetch priority; never lazy-load it.
- +Serve modern formats (AVIF, WebP) at the right size for each screen.
- +Do not hide hero content behind JavaScript animations that start at opacity 0.
- +Render pages statically and serve them from a CDN close to your users.
Fixing INP
- +Ship less JavaScript: remove unused libraries and load non-critical code after the page is idle.
- +Break up long tasks and avoid heavy work in event handlers.
- +Prefer CSS transitions over JavaScript animation libraries where possible.
Fixing CLS
- +Always set width and height (or aspect ratio) on images, videos and embeds.
- +Self-host fonts with size-adjusted fallbacks to avoid text reflow.
- +Reserve space for banners, sliders and ads before they load.
Lab scores vs real users
Lighthouse and PageSpeed lab scores simulate a slow phone and are useful for debugging, but Google ranks on field data from real Chrome users, shown in Search Console's Core Web Vitals report. Aim to pass all three metrics for at least 75% of real visits.
Frequently asked questions
Do Core Web Vitals affect Google rankings?
Yes, as part of Google's page experience signals. They rarely outrank relevance, but they can decide close contests and strongly affect conversion rates.
Why is my mobile score lower than desktop?
Lab tests simulate a mid-range phone on a slow 4G connection, so JavaScript and image weight cost far more on mobile.
What replaced FID?
Interaction to Next Paint (INP) replaced First Input Delay (FID) as a Core Web Vital in March 2024.
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