IMVASA

Free Image SEO Checker

List every image on a page with its alt text and dimensions, then test file size, format, broken images and lazy loading. Free, no account.

Enter any page. Its images are listed and a sample of the files is fetched.

What Makes an Image SEO-Friendly

  • Alt text that describes the image, or an empty alt for decoration.
  • A descriptive file name, such as cold-brew-ratio.jpg rather than IMG_2041.jpg.
  • The right size and format: resized to how it's displayed, compressed, and served as WebP or AVIF.
  • Width and height attributes, so the page doesn't jump as images load.
  • Lazy loading below the fold, never on the main image at the top.

Heavy images are usually what slows Largest Contentful Paint. Measure it with the page speed checker, and check your share image with the Open Graph checker.

How to Check a Page's Images for SEO

  1. 1

    Paste the page URL

    Enter a page with the images you care about: a product page, an article or your homepage.

  2. 2

    Review every image

    Each <img> is listed with its alt text, its width and height, and whether it is lazy-loaded.

  3. 3

    Check the files

    Up to 25 image files are fetched to measure their weight and served format and to catch broken URLs.

  4. 4

    Fix what's flagged

    Write alt text for meaningful images, set width and height, compress heavy files and serve WebP or AVIF.

Check more than the images

The free audit runs these same image checks, plus titles, indexability, schema, links, Core Web Vitals and AI-search readiness.

Image SEO Checker FAQ

Why does alt text matter for SEO?

Alt text is how search engines and AI answer engines understand what an image shows, which is how it ranks in Google Images. Screen readers read it aloud, so it is also an accessibility requirement.

How long should alt text be?

Describe the image in a short sentence, under about 125 characters. Say what's in it and why it's there, and don't stuff keywords.

Should decorative images have alt text?

Give them an empty alt attribute, alt="". Screen readers then skip them. Leaving alt off entirely is different: some screen readers read out the file name instead.

What image format is best for SEO?

WebP and AVIF are usually far smaller than JPEG or PNG at the same quality, and Google indexes both. Smaller files load faster, which helps Largest Contentful Paint.

Should I lazy-load every image?

No. Lazy-load images below the fold, but not the main image at the top of the page. Lazy-loading the hero image delays Largest Contentful Paint. Give it width and height and, if it's the largest element, fetchpriority="high".

Is the image SEO checker free?

Yes, with no signup.

Need to check more than one issue? Run our free SEO audit tool for 210 automated SEO and AI search checks, with evidence and priority fixes in a shareable report. No email or signup required.