Synonyms: Alternative text Alt attribute Image description
An alt tag (or alt attribute, alt text) is an HTML attribute used to describe the content of an image on a webpage. Alt tags are primarily used to provide alternative text for images, which helps in two key ways: improving accessibility for users with visual impairments and enhancing SEO by giving search engines more context about the image content.
When an image fails to load, the alt tag’s text appears in its place, explaining what the image is supposed to show. Screen readers also rely on alt tags to describe images for visually impaired users, ensuring that the content is accessible to everyone.
In terms of SEO, alt tags help search engines better understand what an image is about, since search engines can’t “see” images the way humans do. Descriptive, keyword-rich alt text can improve a website’s visibility in image search results.
Here’s a simple example of an alt tag in HTML:
<img src="dog-photo.jpg" alt="Golden Retriever playing in the park">
In this case, the alt text provides a clear description of the image, benefiting both users and search engines.