Cumulative Layout Shift (CLS)

Cumulative Layout Shift measures unexpected movement of page content as it loads. Images without dimensions are a top cause. This category covers width/height attributes, aspect-ratio, and reserving space.

Cumulative Layout Shift (CLS) 5 min read

Prevent Layout Shifts: Set Width & Height Attributes Correctly

Learn how to correctly set width and height attributes on images to maintain aspect ratios and prevent layout shifts during loading, improving Core Web Vitals scores.

June 7, 2026