PDF files are in many cases the only way for website visitors to access certain content. They are the best file option for making secure and downloadable documents, for printing documents that need to keep a format, for providing a high level of detail in documents, and for creating interactive forms, as well as documents with low usage. Therefore, the importance of making PDFs accessible to everyone should not be underestimated.

For a document to be accessible it has to contain information and content that all users can access, read, and understand, regardless of disabilities. Preferably in a way that doesn’t require a time-consuming remediation tool.

Here are some best practices for making PDFs accessible:

  • Define the language the document is published in.
  • Provide the document with a descriptive title.
  • Use built-in features within the authoring tool, commonly called tags, to define headings, paragraph texts, lists, tables, alternative text for images etc.
  • Ensure that the document has a proper reading order so that users with assistive tools can access the document.
  • Create bookmarks for everyone to get an index and overview.
  • Make sure you use ‘Save as’ or ‘Export to PDF’ in a way that keeps tags in the document.
  • Check the PDF after conversion by using an accessibility checker such as Siteimprove Accessibility.
  • Make sure the security settings of the document allow for assistive technologies to extract text.

So does this cover all possible accessibility issues that may be present in a document? No, but it does address major PDF accessibility areas and will ensure that most users are able to access and read your PDFs. My personal mantra is “Better to be accessible to 90 % of your users than to 60 % of your users!”

To promote usage of PDF files the Matterhorn Protocol was created, which outlines a group of 31 checkpoints with 136 possible failure points when creating a PDF. Although PDFs are not recognized by W3C, the best guidelines to fulfil the criteria for accessible PDFs are addressed by the 23 WCAG PDF Techniques. Keep in mind that compliance to the Matterhorn Protocol does not automatically ensure that you comply to WCAGs accessibility standards. So when you create a PDF, you should keep in mind that:

  • HTML achieves accessibility better than PDF.
  • Most PDFs on the web should be HTML.
  • Many websites have a ‘Print to PDF’ feature.
  • Some documents (Word, Excel, etc.) should be created as PDFs before uploaded to a website.