We scan large samples of real websites with the same engine that powers our scanner, then publish the aggregate findings. Original data on how the web actually handles images — no site is ever named; every figure is framed as "of the sites we tested."
·883 sites tested
Across 883 sites and 25,546 images measured in a real browser, 49.8% of measurable images are more than 4x larger in area than the slot they render into, and 35.4% of HTML images have no alt text.
·44 sites tested
We measured every image on 44 popular sites in a real browser. 68% ship at least one oversized image, and 45% of all measurable images are larger than the box they render into.
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