MediaSimple mode
Images
Audits images on the page to detect outdated formats, missing dimensions, incorrect lazy loading, and problems affecting the most important visual content.
Why it matters
Images are often the heaviest resource type on a page and they frequently decide whether the page feels fast or sluggish. A badly loaded hero image can hurt LCP, while missing dimensions can trigger layout shifts.
Where to run it
Available automatically in Simple mode.
Can also be explored in more depth from the underlying WebPerf Snippets reference.
Open analyzerWhat you learn from this test
Whether key images are oversized or use inefficient formats
Whether images are missing intrinsic dimensions
Whether lazy loading is being applied to above-the-fold content
Common fixes
Serve modern formats such as WebP or AVIF where practical
Set width and height attributes to reduce layout shifts
Avoid lazy loading the hero image
Compress, resize, and prioritize the most visible images