Digital accessibility: creating accessible text
Certain file types, including PDFs, may contain images of text that assistive technologies like screen readers cannot access. It is important to check your files to make sure that text is machine readable and to include alternative text any time that text is part of an image.
PDFs
Text in PDF documents may not be machine readable. If you're not sure whether your PDF is accessible, try using your cursor to select text. If you cannot select a line of text, your file is not accessible.
Even if you can select text, your PDF is likely to have other accessibility issues. You must have Acrobat Pro to confirm that a PDF is fully accessible. For this reason, we recommend against using the PDF format unless you have no other option.
Scanned documents
PDFs created by scanning print documents are not accessible without further editing.
Saving text documents as PDFs
Many different types of document creation software allow you to save your document as a PDF. Often these options do not result in an accessible document. In particular, options that are meant to produce a print document, such as printing to PDF, will produce an inaccessible PDF. For this reason, we recommend sharing the original text document rather than a PDF.
It is possible to create an accessible PDF by starting with a fully accessible Word document.
Do not use the option to print as a PDF to create a PDF document from Word. This will result in an inaccessible document.
Text that is part of an image
Sometimes, text is included as part of an image. This text is not accessible to screen readers and must be described in the text surrounding the image or in the alternative text. Common examples of images with inaccessible text are
- Screenshots of text
- Posters or other advertising materials created primarily for print but also shared digitally
- Diagrams or graphs that include text labels
To create accessible text content
- Avoid using screenshots to share text. Instead, copy or scan text into an accessible document.
- Include any text contained in an image in body text. For example, if you are sharing an image of a poster for an event via email, also include information about the event in the body of the email. For many diagrams or graphs, a caption or legend may include some of the textual information contained in the image.
- All images require alternative text. If the text contained in your image does not appear in accompanying text, such as a caption, include it in the alternative text. If textual information in the image is shared elsewhere, include information about where to find it in the alternative text. For example, alternative text for an event poster might be “Poster advertising the Biology Open House. Event details can be found in the accompanying email.”