Explaining Alt tags

An ALT tag (or alternative tag) is a written descriptor of an image (whether it be a logo or a photograph or some other image).

The Alt attribute or Alt text is used to provide a text alternative for those with reduced functionality as well as for those users who may have vision impairment. All images must have the Alt attribute filled in to reach AA compliance.

Note: Alt text does not generate a tool tip when you hover over the image. This is the Title attribute.

The following points should always be considered:

• Should be accurate and equivalent
• Should be succinct
• Should NOT use the phrase ‘image of…’ or ‘graphic of…’
• Alt text does not refer solely to the Alt attribute of the image tag.
• Alt text may appear in the Alt attribute or in the surrounding text.
• If the image contains a caption do not use the same caption for the alt text. Use a short and concise description.
• When uploading an image, the alt text should be as descriptive as possible.
• When placing the image into your page, you can alter the Alt attribute so that it correctly reflects the context of the page.

Alt text for standard images

• If the image contains a detailed caption then a brief Alt text description is acceptable. If your image enhances content in anyway then there should always be an alt text description.
• If the image is enhancing text, does not include a caption and is not directly described in the content then you may need to include a more detailed description in the Alt attribute.
• An image is only decorative if it is for design purposes only.

Alt text for hyperlinked images (functional images/icons)

• Determine whether the image has a function (if it is hyperlinked) or whether it presents content. If the image has a function then the Alt text should reflect what that function is.
• If an image is hyperlinked then it should provide an explanation of where the link will take you. It is a good idea to use the Title attribute here as well to clarify for the user where they will go. (See page xx for further information on
  Title attribute)

Example: Where the University of Newcastle logo is hyperlinked the alt text should read ‘The University of Newcastle, Australia’.

Alt text for profile images

All profile images should be the full name and title of the person in the image.

Decorative images

If the image does not support your content in any way, that is, if it is purely aesthetic, then it is acceptable to select decorative only.