Core Web Vitals, explained in plain English.
LCP, INP, CLS — three scores that decide your rankings and your conversions. Here's what they actually measure and how to ace all three.
Three numbers that decide your fate
Google boils user experience down to three numbers. Nail them and you're in the green band — where the traffic and conversions live.
Largest Contentful Paint
How fast the main content — hero image, headline — finishes loading. Aim under 2.5 seconds.
Good: ≤ 2.5sInteraction to Next Paint
How quickly the page responds to taps and clicks. Aim under 200 milliseconds.
Good: ≤ 200msCumulative Layout Shift
How much the layout jumps as content loads. Aim below 0.1 — zero is perfect.
Good: ≤ 0.1Speed is a strategy, not a nicety
Core Web Vitals aren't just a checklist — they're competitive advantages that directly impact conversions and AI search engine visibility.
It's a ranking factor
Core Web Vitals are part of Google's page experience signals. Two pages with equal content — the faster one ranks.
It's a conversion lever
Every extra second of load time measurably drops conversions. Speed is a feature your visitors feel before they read a word.
It's an AI-readability signal
AI crawlers often skip slow, JS-heavy pages. A page that loads instantly and ships clean HTML is far more likely to be summarized and cited.
Why your site is slow — and the fix
Slow sites almost always share the same four problems. Here's each one, and the structural fix.
Unoptimized images
Auto-resize, convert to modern formats, and lazy-load below the fold.
Render-blocking scripts
Ship static HTML. No framework bundle standing between the user and your content.
Layout shift from ads & embeds
Reserve space for every element before it loads. Nothing jumps, ever.
Bloated page builders
Static-first output — bytes on a CDN, not a JavaScript app pretending to be a page.
Quick answers
Three metrics Google uses to measure user experience: LCP (how fast the main content loads), INP (how quickly the page responds to interaction), and CLS (how much the layout shifts). They're a ranking signal and a direct proxy for how visitors experience your site.
LCP under 2.5s, INP under 200ms, and CLS below 0.1. Pass all three and you're in the 'good' band. Static sites typically hit these easily because there's so little to load.
Usually one of four things: unoptimized images, render-blocking JavaScript, layout shift from ads or embeds, or a page builder that outputs heavy code. All four are structural — fixing them means changing how the page is built, not tuning it.
Yes. Core Web Vitals are an official ranking signal, and faster pages also earn more links and shares. On equal content, speed is often the tiebreaker.
Makr pages are static HTML on a global CDN with automatically optimized images — so they typically score 100 on Lighthouse with perfect LCP, INP, and CLS out of the box.