Performance Guide

Core Web Vitals Optimization for Better SEO

Master LCP, CLS, and INP metrics to improve your website's performance and Google search rankings. Complete guide with practical optimization techniques for 2025.

12 min read
Intermediate
SEO Critical

What are Core Web Vitals and Why They Matter for SEO

Core Web Vitals are Google's key metrics for measuring user experience on websites. Since 2021, these metrics directly impact your search rankings as part of Google's page experience signals.

LCP

Largest Contentful Paint

Measures loading performance

Good: ≤ 2.5s

CLS

Cumulative Layout Shift

Measures visual stability

Good: ≤ 0.1

INP

Interaction to Next Paint

Measures interactivity

Good: ≤ 200ms

Largest Contentful Paint (LCP) Optimization

LCP measures how long it takes for the largest visible element to load. This is often your hero image, header text, or main content block. Optimizing LCP is crucial for first impressions.

Proven LCP Optimization Techniques

Image Optimization

  • Use WebP or AVIF formats for better compression
  • Implement lazy loading for below-fold images
  • Add fetchpriority="high" to LCP images
  • Use responsive images with srcset

Server & Hosting

  • Use a fast CDN for global content delivery
  • Enable HTTP/2 and HTTP/3 protocols
  • Implement browser caching strategies
  • Minimize server response times (TTFB)

Quick LCP Optimization Code Example

<!-- Optimize hero image for LCP -->
<img
src="hero.webp"
fetchpriority="high"
loading="eager"
width="800" height="600"
alt="Hero image"
/>

Cumulative Layout Shift (CLS) Optimization

CLS measures visual stability by tracking unexpected layout shifts. Poor CLS scores frustrate users and harm conversions. Here's how to eliminate layout shifts completely.

Common CLS Issues and Solutions

❌ Problem: Images without dimensions

Images load and push content down, causing layout shifts.

✅ Solution:

Always set width and height attributes, or use aspect-ratio CSS

❌ Problem: Web fonts loading

Font swapping causes text to jump and resize.

✅ Solution:

Use font-display: swap and preload critical fonts

❌ Problem: Dynamic content injection

Ads, banners, or widgets load and push content around.

✅ Solution:

Reserve space for dynamic content with min-height

CLS-Safe CSS Techniques

/* Reserve space for images */
.image-container {
aspect-ratio: 16 / 9;
width: 100%;
}
/* Prevent font layout shift */
@font-face {
font-display: swap;
}

Interaction to Next Paint (INP) Optimization

INP replaced First Input Delay (FID) in 2024 and measures how quickly your website responds to user interactions like clicks, taps, and keyboard inputs throughout the entire session.

INP Optimization Strategies

JavaScript Optimization

  • Reduce JavaScript bundle sizes
  • Use code splitting and lazy loading
  • Minimize main thread blocking tasks
  • Use Web Workers for heavy computations

Interaction Patterns

  • Provide immediate visual feedback
  • Debounce expensive operations
  • Use requestAnimationFrame for smooth animations
  • Optimize event handlers

Tools to Measure and Monitor Core Web Vitals

Google Search Console

Real user data from actual visitors to your site

Free

Google Lighthouse

Lab data and actionable optimization suggestions

Free

PageSpeed Insights

Combined lab and field data with recommendations

Free

Web Vitals Extension

Real-time metrics while browsing any website

Chrome

GTmetrix

Detailed performance analysis and monitoring

Freemium

WebPageTest

Advanced testing with different locations and devices

Free

dplooy.com: Optimized for Core Web Vitals

Our hosting platform is built with Core Web Vitals optimization in mind

Built-in Performance Features

  • Global CDN

    Optimized LCP with worldwide content delivery

  • Automatic Image Optimization

    WebP conversion and proper sizing for better CLS

  • Optimized Servers

    Fast response times for better INP scores

  • Mobile-First Design

    Optimized for mobile Core Web Vitals

Performance Monitoring

  • Real-Time Analytics

    Monitor your Core Web Vitals performance

  • Performance Alerts

    Get notified when metrics degrade

  • Optimization Suggestions

    AI-powered recommendations for improvements

Your Core Web Vitals Action Plan

1

Audit Your Current Performance

Use Google Search Console and PageSpeed Insights to establish baseline measurements for your Core Web Vitals.

2

Prioritize Quick Wins

Start with image optimization, add proper dimensions, and implement lazy loading for immediate LCP improvements.

3

Implement Systematic Changes

Address CLS issues with proper spacing, optimize JavaScript for better INP, and establish monitoring systems.

4

Monitor and Iterate

Continuously monitor your Core Web Vitals and make data-driven optimizations for sustained SEO benefits.

Ready to Optimize Your Core Web Vitals?

Start hosting with a platform that prioritizes performance and SEO optimization