Optimize LCP with fetchpriority in Images: Boost Your Core Web Vitals

How fetchpriority attribute in Images Helps Optimize LCP and Improve Core Web Vitals

As site speed becomes increasingly vital for both SEO and user experience, developers and SEO experts are focusing more on optimizing Core Web Vitals, especially Largest Contentful Paint (LCP). One modern and effective way to do this is by using the Fetchpriority Attribute in your image tags.

What is the Fetchpriority Attribute in HTML?

The Fetchpriority Attribute allows developers to control the browser’s loading behavior by prioritizing critical resources like images. It works alongside other performance-related attributes like loading, decoding, and even rel="preload" for better loading strategy.

Syntax example:

<img src="hero.jpg" fetchpriority="high" alt="Hero image">

Possible values:

• high – Load as a high-priority resource
• low – Load as a low-priority resource
• auto – Let the browser decide

Learn more in Google’s fetchpriority documentation
Also read: Image Optimization Best Practices on web.dev

How the Fetchpriority Attribute Impacts LCP

LCP measures how long it takes for the largest visible content element (usually an image or heading) to fully render. Slow LCP scores often result from delayed image loading, especially on image-heavy landing pages.

By setting fetchpriority="high" on your hero image (or the image contributing to LCP), you signal the browser to download it earlier, improving perceived performance and reducing LCP time.

Real-World Impact

According to Google’s own Web.dev guidance, marking your LCP image with fetchpriority="high" can reduce LCP by 100–300ms on average — enough to shift a page from “needs improvement” to “good” in Core Web Vitals assessments.

Best Practices

• Use fetchpriority="high" only on one image per page — typically your LCP element.
• Combine with loading="eager" and decoding="async" for best results.
• Avoid overusing it — too many high-priority assets can cause resource contention.

Example:

<img
  src="banner.webp"
  alt="Homepage banner"
  fetchpriority="high"
  loading="eager"
  decoding="async"
/>

SEO & Performance Boost

Since Google includes Core Web Vitals in its page ranking signals, optimizing LCP directly translates to better SEO. Improving your image loading strategy not only speeds up load time but also enhances user engagement, bounce rate, and mobile performance.

Final Thoughts

Using the fetchpriority attribute is a low-effort, high-impact technique to enhance page load speed and improve your LCP score. Combined with other performance practices like image compression, lazy loading, and CDN delivery, it becomes a powerful tool in your web performance and SEO strategy.

Want to Learn More?

If you’re interested in mastering techniques like the Fetchpriority Attribute, optimizing Core Web Vitals, and building blazing-fast websites, we invite you to join our 8-month Web Development Course. This hands-on program covers everything from HTML and CSS to advanced performance optimization, SEO strategies, and real-world project development.

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