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ahmed isam
ahmed isam

Posted on Originally published at image-compressor-saas.shop

Fix LCP with Images: Core Web Vitals Tutorial

#lcp #corewebvitals #imageoptimization #webperf

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title: Fix LCP with Images: Core Web Vitals Tutorial
description: optimize images lcp core web vitals
tags: [lcp, core web vitals, image optimization, web performance]

canonical_url: https://image-compressor-saas.shop/en/blog/core-web-vitals-fix-lcp-images

Largest Contentful Paint (LCP) measures how long it takes for the largest content element on your page to become visible. Google considers an LCP of 2.5 seconds or less as good. Since images are often the largest content element, they're frequently the culprit behind poor LCP scores.

Common LCP Image Problems

  1. Oversized images: Files that are larger than needed for their display size
  2. Slow loading: Images that take too long to download
  3. Render-blocking: Images that delay page rendering
  4. No lazy loading: Above-the-fold images loaded immediately

How to Fix LCP with Images

1. Resize Images to Display Dimensions

Don't serve a 4000px wide image when it displays at 800px. Resize to the actual display size plus a bit for retina displays (2x).

2. Use Modern Formats

Convert images to WebP or AVIF format. These provide 25-35% smaller file sizes than JPEG/PNG with similar quality.

<picture>
  <source srcset="image.webp" type="image/webp">
  <img src="image.jpg" alt="Description">
</picture>
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3. Implement Lazy Loading

For images below the fold, use lazy loading:

<img src="image.jpg" loading="lazy" alt="Description">
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Note: Above-the-fold images should NOT be lazy loaded—they block LCP.

4. Preload Critical Images

For your LCP image, use preload:

<link rel="preload" as="image" href="hero-image.jpg">
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5. Optimize Image Delivery
  • Use a CDN for faster delivery
  • Implement responsive images with srcset
  • Compress images without visible quality loss
  • Consider image optimization services

Measuring LCP Improvements

Use tools like:

  • Google PageSpeed Insights
  • Chrome DevTools Lighthouse
  • WebPageTest

Test before and after optimizations to measure impact.

Try our image compressor at image-compressor-saas.shop.

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