What is Alt Text?
Alt text is the descriptive HTML attribute on an image that screen readers announce and search engines read. Alt text improves accessibility and helps images rank in image search.
Why Alt Text matters
The alt attribute is what a screen reader speaks when it reaches an image, what a browser shows when the file fails to load, and what a search engine reads to understand and rank the picture. Good alt text describes the content and function of the image in its context: what a sighted reader gets from it, in one sentence. Decorative images get an empty alt="" so assistive technology skips them, which is different from omitting the attribute.
Because it is indexed, alt text is also an SEO signal for image search and a small one for the page, but writing it for keywords instead of people produces the stuffed strings that both users and Google dislike. Describe the image; if the product name belongs in the description, it will be there naturally.
Example
Three images, three treatments:
<img src="chart.png" alt="Line chart: LCP fell from 4.1 s to 2.2 s after image compression">
<img src="divider.svg" alt="">
<img src="hero.jpg" alt="Founder at a desk reviewing an audit report on a laptop">The chart alt states what the chart shows; the divider is decorative; the hero describes the scene.
Common mistakes
- •Starting with 'image of' or 'picture of'; the screen reader already announces it as an image.
- •Omitting the attribute entirely, so the file name gets read out instead.
- •Keyword lists ('seo audit tool website audit free audit') instead of a description.
How Webmatik checks it
The Image alt text check appears in both the SEO and Accessibility categories: it counts images on each audited page and reports how many lack an alt attribute, with the offending elements listed so they can be fixed.
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