Understanding Core Web Vitals for your website

Google measures three specific aspects of how your website performs for real visitors. These measurements are called Core Web Vitals, and they directly influence where your site appears in search results. This guide explains each one in plain terms.

What are Core Web Vitals?

Core Web Vitals are three metrics that Google uses to assess how fast, responsive, and visually stable your website is. They measure the experience a real person has when loading and interacting with your pages.

You can see your LCP and CLS scores in the Performance tab of the Web60 portal. Google Search Console also reports on all three metrics using data from actual visitors.

LCP: Largest Contentful Paint

LCP measures how long it takes for the main content of your page to become visible. In practice, this is usually the largest image or block of text that appears on screen when the page first loads.

Think of it as the answer to: "How long does a visitor wait before they can see what the page is about?"

Targets:

• Good: under 2.5 seconds
• Needs improvement: 2.5 to 4 seconds
• Poor: over 4 seconds

The most common causes of a slow LCP are oversized images, a slow server response, or render-blocking scripts that delay the page from appearing.

INP: Interaction to Next Paint

INP measures how quickly your website responds when someone interacts with it. If a visitor taps a button, clicks a link, or types in a form field, INP measures the delay between that action and the page visually responding.

Think of it as: "Does the site feel snappy or sluggish when I click things?"

Targets:

• Good: under 200 milliseconds
• Needs improvement: 200 to 500 milliseconds
• Poor: over 500 milliseconds

Slow INP is usually caused by heavy JavaScript processing that blocks the browser from updating the screen. Sites with many active plugins or complex animations are more likely to have INP issues.

CLS: Cumulative Layout Shift

CLS measures how much the visible content on your page moves around unexpectedly while it loads. A layout shift happens when an element on the page changes position after it has already appeared.

A common example: you start reading text on a page, then an image loads above it and pushes the text down. That jump is a layout shift.

Targets:

• Good: under 0.1
• Needs improvement: 0.1 to 0.25
• Poor: over 0.25

The most common causes are images without specified width and height dimensions, web fonts that load late and change the size of text, and content that is injected into the page after the initial load.

How to improve your Core Web Vitals

For most small business websites, a few straightforward steps make the biggest difference:

1. Optimise your images. Resize them to the dimensions they display at, compress them, and use WebP format. This directly improves LCP.
2. Keep plugins to a minimum. Every active plugin adds JavaScript and PHP processing. Remove any you are not actively using. This helps both LCP and INP.
3. Set image dimensions. Make sure your images have width and height attributes so the browser knows how much space to reserve. This reduces CLS.

You do not need to understand the technical details behind these metrics to act on them. Focus on the practical steps above, and check your scores in the Web60 portal to track your progress.