The Image Alt Text Checker lists how many images a page has and how many are described, decorative or missing alt text. It fails images with no alt attribute or with a filename as the alt text, and warns on descriptions under 8 characters. Images missing alt text are listed by source, up to 20. Images with empty alt text count as decorative.
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The headline is either All images described or the number of images with no alt text out of the total. The stats split the images into described, decorative and missing.
The tool reads the HTML the server sends, so images that JavaScript adds after the page loads are not counted.
Every image has an alt attribute fails when any image has no alt attribute at all. Alt text is not a filename fails when the alt text looks like a file name, such as IMG_2041.jpg. Alt text is descriptive warns when a description is under 8 characters.
An image with alt="" is counted as decorative and passes. That is the right choice for a spacer, a divider or an icon next to text that says the same thing. The Described count is everything that is neither missing nor decorative, so it can include short or filename-style text that the checks flag separately.
Describe what the image shows and why it is there, the way you would to someone who cannot see it. "Founder presenting the quarterly dashboard to the sales team" works better than "team" or "dashboard.jpg". Skip phrases like "image of". If the image is a chart, say what it shows.
Peak Answer runs checks like these every week, then writes the content and gets the placements.