<img Decoding="async" Class="alignleft" Src="ht... Apr 2026

: For the Largest Contentful Paint (LCP) image—usually the main hero image—using decoding="async" can actually delay its appearance, potentially hurting your Core Web Vitals scores.

: Moving the decoding process to a background thread keeps the main thread free, ensuring a smoother user experience and reducing "jank" while scrolling. <img decoding="async" class="alignleft" src="ht...

While async decoding is generally a best practice for secondary images, it can occasionally backfire for critical "above-the-fold" content: : For the Largest Contentful Paint (LCP) image—usually

249: Decoding async, tree rings, and flexbox gap - CSS-Tricks and flexbox gap - CSS-Tricks