File Optimization
Image file optimization directly affects page load performance. Large image files slow page load times; missing width and height attributes cause layout shifts as images load. These two checks identify the most common image optimization failures that impact both performance and Core Web Vitals.
Oversized Image Files
Warning
Image file size is too large — slowing page load and hurting Core Web Vitals.
Missing Image Size Attributes
Notice
Images without width/height attributes cause layout shift (CLS) as they load.
Audit image optimizationacross your site
The audit identifies oversized images and missing size attributes across all pages.