a11yTips

Provide replacement text for PDF links that are not meaningful

no. 126

Make sure links in PDF documents that are not meaningful are given an alt text value

As a general rule, links in documents are expected to be meaningful and convey information about their purpose or where they will lead. This is mainly to ensure that screen reader users who cannot see the link in its context can still figure out what the link is about. Consequently, links such as “click here” and “read more” can often be a problem. Descriptive links are always better when it comes to accessibility, but if a link remains meaningful within its immediate context, screen reader users will always be able to refer to the context to understand what the purpose of a link is. When this is not possible, or when the link is not meaningful within its immediate context, authors are expected to provide additional information, so the purpose of the link does become descriptive and meaningful.

To do so, simply assign an alt text value to the link. Contrary to HTML, where alt text values can be added to non-text content such as images and graphic controls, any PDF object can be assigned an alt text value. Whenever such an alternative is provided, screen readers will use it to override the default information. Hence, in the case of links that lack meaning or description, replacing the screen text with meaningful alternate text for links will make links more accessible. This can be done by right clicking on the properties of any given link form the tag tree and simply assigning a value to the “Alternate Text” field under the Tag tab.

User Story

As a visually impaired user using assistive technology, I want every link I encounter in a PDF document to be meaningful, so that I can reliably determine where the inks will lead.

Simple Code Example

Not Applicable

Testing Methodology

Using Adobe Acrobat Pro, look for links that poorly convey their purpose and looking at the properties of the link in the tag tree, validate that it has been assigned a more descriptive and meaningful value through the alternate text field.

Specification Details