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Language, color, reading size, and motion stay on this device.

Inspect URLAdd website

Image SEO · source declarations + HEAD metadata

Inspect image alternatives, dimensions, responsive markup, URLs, and delivery headers

Discover images in one public HTML response, group repeated URLs without losing their source declarations, then check selected targets for HTTP state, redirects, content type, declared length, cache policy, validators, and last-modified metadata.

UNIQUE URLS50 MAXCONCURRENCY3 CHECKSTARGET METHODHEAD

HEAD checks do not download image bodies. A declared Content-Length is not a measured transfer size, and an empty alt can be correct for a decorative image.

IMG

Ready for a public HTML page.

No sample images, estimated compression savings, visual-quality grade, or synthetic performance result is displayed.

Image review practice

Combine markup, response, and rendered evidence

Name meaningful images

Use concise contextual alternative text for informative images. Use an empty alt only when the image is genuinely decorative in that context.

Reserve layout space

Width and height attributes can establish an aspect ratio before the image loads. Confirm computed sizing and layout behavior in a browser.

Measure the selected resource

Use browser tooling to see which srcset candidate was chosen, its actual transfer, decoding, cache behavior, and whether it participates in LCP.

Google image SEO guidanceweb.dev layout-shift guidanceMDN image reference