critical-images
// Use when reviewing image assets, markup, and CDN or build transforms related to Prioritize loading critical images. Check encoded size, rendered size, loading strategy, and above-the-fold impact together.
Prioritize loading critical images
The Largest Contentful Paint (LCP) is often an image—prioritizing its load can improve LCP by 20-40%, directly impacting Core Web Vitals and SEO.
Quick Reference
- Use fetchpriority='high' on LCP images
- Preload hero images in document head
- Remove loading='lazy' from above-the-fold images
- Critical images directly impact LCP Core Web Vital
Check
Identify which images are critical for initial render and ensure they load with high priority.
Fix
Add fetchpriority='high' to critical images and use preload for hero images.
Explain
Explain how prioritizing critical images improves Largest Contentful Paint (LCP).
Code Review
Review image assets, markup, and delivery configuration related to Prioritize loading critical images. Flag exact files or components where format choice, sizing, or loading behavior violates the rule, and describe how to confirm the fix in DevTools.
For full implementation details, code examples, and framework-specific guidance,
see references/rule.md.
Rule page: https://frontendchecklist.io/en/rules/images/critical-images