Alt text on a linked image describes the action
Accessibility
Alt text must always appear on an image which is being used as a link.
Reason
Although not every image needs to have alt text, if the image is being to link to something, it must have alt text which describes the effect of clicking on the link. This is so a user with a screen reader doesn’t have a “wasted journey”.
Best practice
This image is a link to the MacOdrum Library. This means that the image must have alt text to outline what will happen if the user clicks on the image. In this instance it reads:
Discover more information about the MacOdrum Library.
Example of less accessible practices
This image has no alt text. (Worse still: it conveys the message in text on the image.)
This means the user with a screen reader does not know what the link will do, and that entire URL will be read out to them.
Additional benefits
- Usability: If there is no alt text then if an image doesn’t render then the user is uncertain as to what will happen if the link is clicked.
- SEO: Alt text improves SEO.
- Marketing: Features that improve the usability of a site make it easy to navigate and lead to users staying longer.
What WCAG says
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