Core Web Vitals: Why Speed Matters

Most of your visitors arrive on a mobile phone, often on a patchy connection. If the page is slow or jumps around while loading, they leave — and Google notices. Core Web Vitals are Google's way of measuring that experience.

The three Core Web Vitals

• Largest Contentful Paint (LCP) — how quickly the main content appears. Good: 2.5 seconds or less.
• Interaction to Next Paint (INP) — how quickly the page responds when someone taps or clicks. Good: 200 milliseconds or less. INP replaced First Input Delay in March 2024.
• Cumulative Layout Shift (CLS) — how much the layout jumps while loading. Good: 0.1 or less.

Google assesses these using real-user data from Chrome, measured at the 75th percentile. In other words, most of your real visitors need a good experience — not just you on office Wi-Fi.

Why it matters for business

Page experience is one of many ranking signals, so speed alone will not push weak content to the top. But between comparable pages it can be the tie-breaker, and its effect on conversions is direct: faster pages keep more visitors, and more visitors become enquiries.

The fixes with the biggest impact

Improve LCP

• Serve images as WebP or AVIF, sized for the screen they are shown on.
• Do not lazy-load the main hero image; do lazy-load images further down the page.
• Use good hosting with a CDN and render the main content in the initial HTML.

Improve INP

• Reduce and defer JavaScript, especially third-party chat, tracking and widget scripts.
• Split large bundles so each page loads only the code it needs.

Improve CLS

• Set width and height on images and video embeds.
• Reserve space for banners and ads instead of inserting them above content.
• Load web fonts with a sensible fallback to avoid text jumping.

How to check your site

Run your key pages through PageSpeed Insights and review the Core Web Vitals report in Google Search Console. Focus on the field data (real users) first.

Need a faster site? Our web development team builds performance in from day one. Request a site audit.