Core Web Vitals are Google's three key measurements of page experience. They affect your search rankings — but more importantly, they directly affect whether visitors stay on your site and take action.
Here's what each one means, why it matters, and what it looks like when it's broken.
LCP — Largest Contentful Paint
LCP measures how long it takes for the largest visible element on your page to load. Usually that's a hero image, a heading, or a video.
What it means for users: When LCP is slow, visitors stare at a blank or partially loaded screen. Many leave before the page finishes rendering.
What it means for business: A slow LCP means higher bounce rates. Visitors who leave before the page loads never see your offer, your form, or your phone number. You lose the lead before you even had a chance.
Good target: Under 2.5 seconds.
INP — Interaction to Next Paint
INP measures how quickly your page responds when a user interacts with it — clicking a button, tapping a menu, filling a form. It replaced FID (First Input Delay) in 2024.
What it means for users: When INP is poor, the site feels sluggish. Buttons don't respond. Menus lag. Form fields take a moment to accept input. It feels broken even when it technically works.
What it means for business: A visitor who clicks your "Get a Quote" button and waits 300ms for something to happen might click again, get confused, or assume the site is broken. On mobile, this is even worse — slow interaction feels like the site doesn't work.
Good target: Under 200 milliseconds.
CLS — Cumulative Layout Shift
CLS measures visual stability. It tracks how much elements on the page move around after the page loads.
What it means for users: You've experienced this: you go to click a link, and right before your finger lands, an image loads above it and pushes the link down. You click the wrong thing. Or you start reading a paragraph and it jumps down the page.
What it means for business: Layout shift causes accidental clicks, frustration, and a feeling that the site is low quality. It directly hurts conversion because users lose trust in a site that feels janky.
Good target: Under 0.1.
Why This Matters Beyond SEO
Google uses Core Web Vitals as a ranking signal. But the bigger reason to care is conversion. Every second of load time, every sluggish interaction, every layout shift costs you visitors and leads.
A fast, stable, responsive site doesn't just rank better — it converts better. Visitors trust it more, stay longer, and complete forms more often.
What to Do About It
If you're not sure where your site stands, run it through Google's PageSpeed Insights tool. It'll show you your Core Web Vitals scores and tell you exactly what's slowing you down.
Common fixes include compressing images, reducing JavaScript, using a CDN, preloading key resources, and setting explicit dimensions on images and ads to prevent layout shift.