• Alternative text
• Analytics
• Duplicate content
• Facebook page
• Facebook sharing
• Feeds
• Headings
• Images
• Incoming Links
• Inoffensive content
• Layout
• Links
• Meta tags
• Popularity
• Printability
• Semantic HTML
• Social Media
• Titles
• Trustworthiness
• URL format
• Visual Interest
• W3C compliance

The alternative text test checks each image tag on a page for the presence of an alt attribute.

Why do we test for this?

Most visitors to your site will have a visual browser which will display the page, but some may use a screen-reader or a text only browser.  These visitors cannot see the image as someone with a visual browser would, and so rely on the alternate text to understand what the image is.  Inclusion of alt text is actually a legal requirement in some countries, and a failure to do so would be considered discriminatory.

How do we test for this?

We look at each image tag on a page and mark a site down if it does not include an alt attribute.

What can I do about it?

Ensure all images on your page include a descriptive alt attribute.  If the image is for layout only or doesn't require an alt attribute, don't omit it.  You must include the alt attribute but there is no problem leaving it empty if there is no suitable alternate description.