PDF Accessibility

The PDF file type was originally created as a way to preserve formatting across platforms and softwares. Because of that, they’re difficult to edit or make changes to. From an accessibility standpoint, it’s better to keep files in their original formats (such as Word Documents and PowerPoints) whenever possible. The following are resources to assist in making existing PDFs as accessible as possible, whether you are creating a new PDF or editing an existing one. 

Creating PDFs

If you’re creating a new PDF, it’s important to make sure the document you’ll be saving as a PDF is accessible in its original format. Check out these specific instructions for creating accessible documents in the most common formats:

Once a document has been made accessible, it can be saved as an accessible PDF. 

  1. Choose File > Save As.
  2. Expand the “File Type” dropdown and choose “PDF (.pdf)”.

Do not use export widgets or plugins, as they don’t preserve the tags needed for PDF accessibility.

Editing Existing PDF Files

If you don’t have access to the original file, use this guide to work with the PDF itself. Keep in mind that most of these adjustments can only be made to high-quality PDFs, as scanned PDFs can’t be made accessible without starting the process from scratch. You can check out this Adobe overview on what makes an accessible PDF. The following instructions are for making adjustments using a common software, Adobe Acrobat DC.

Accessibility Checker

The accessibility tool can be accessed from the toolbar on the right side menu or from the “Tools” tab located at the top of the page.

Adobe acrobat Tools tab with the Accessibility option highlighted in a red box one from the bottom of the menu.

Note: It may need to be added to the toolbar initially. This can be done by choosing “More Tools” then finding the “Accessibility” option in the “Protect and Standardize” section and clicking “Add.” 

Open the Accessibility tool and choose “Accessibility Check,” which will open a dialogue box. Choose “Start Checking” to run the check. A menu will appear on the left side of the screen with a list of issues. Non-issues will be followed by the word “Passed,” while issues needing attention will be preceded by small red or blue icons. More information about any of the items in this list can be found by right-clicking on the item, then clicking “Explain.” Solutions to the most common issues are listed below and you can check out the bottom of this page for more resources, including video walkthroughs.

Title and Language

To fix issues with the document’s primary language and title, go to File > Properties. 

  1. Choose the “Description” tab and update the field labeled “Title” with the desired document title. 
  2. Navigate to the “Initial View” tab. 
    1. In the “Window Options” section, select “Show: Document Title.”
  3. Navigate to the “Advanced” tab.
    1. Under “Reading Options”, update the language field to the correct language.

Reading Order (Tags)

Issues with the tagging of the document will show up as “Tagged PDF” in the “Document” tab of the Accessibility Checker. Tags are labels that define the different types of content in the document. They make PDFs usable with screen readers, and it’s often necessary to fix tagging issues before other accessibility problems can be solved.

To fix this issue, access the tag icon from the Navigation Pane (toolbar on the left side of the window). If it isn’t visible, right click on an empty part of the Navigation Pane and select the tag icon from the list that appears. A list of the tags in the file will be displayed, though in some cases, there may not be any tags in the document.
Tag icon at the bottom of the Navigation Pane in blue, highligted in a red box.

To create or reorder tags, open the Accessibility Tool, and choose “Reading Order” from the menu that appears on the right side of the screen.
Reading order option at the bottom of the Accessibility Tool menu highlighted in a red box.

With the “Reading Order” window open, highlight the desired section of the document, then choose the proper button to add a tag. For example, images should be tagged using the “Figure” button, tables should be tagged using the “Table” button, and paragraph level text should be tagged using the “Text/Paragraph” button. As content is tagged, a tag will appear in the Navigation Pane. You want to make sure that the tags are in the correct reading order, or the order a reader will go through the document.

At this point, alt text should be added to images that need it. To add alt text to a figure, right-click on the tag in the Navigation Pane that corresponds to the image, and choose “Properties”. Alt text can then be added to the designated field. Visit the Alt Text Basics page for general information about creating alt text for images.

Sometimes, PDFs will have an automatically assigned reading order that prevents the file from being tagged correctly. This issue can be identified by opening the “Order” tool in the Navigation Pane and comparing its lists to those in the “Tags” tool. If there’s information contained in the “Order” tool that isn’t present in the “Tags” tool, open the “Order” tool, navigate to the “Options” menu, and “Clear page structure.” This process will have to be redone for each page in the document. The file can then be tagged according to the instructions given above.
Clear page structure option under the options menu in the order tool.

Tables

Tagging tables will help screen readers identify the tables that are found in the document, but sometimes further steps need to be taken to properly identify the various parts of the tables, such as headers. The issues will appear in the accessibility checker under the “Tables” tab as “Headers” and “Summary.”

To fix header problems, open the “Reading Order” tool and ensure that the table is tagged as a table. Next, click the “Table Editor” button, found near the center of the “Reading Order” window. Highlight the table headers, then right-click and choose “Table Cell Properties.” A window will open, where you change the “Type” from “Data Cell” to “Header Cell.” Finally, click “OK.”

To fix a table summary error, with the “Reading Order” tool open, right click on the table and choose “Edit Table Summary.” The summary can then be input in the window that appears. A table summary should explain the content of the table in general terms. 

Lists

Unless lists are formatted correctly, screen readers will read them as regular text. To prevent this, the tagging must be manually changed. You can watch a video walkthrough from KSU for how to fix those.

Tab Order

This error will appear in the accessibility checker in the “Page Content” section. The tab order is what allows a user to use the tab key to navigate the file. This issue can be addressed by opening the “Page Thumbnails” tool from the Navigation Pane. In the menu on the left, select all the page thumbnails (⌘ + A or Ctrl + A), right-click, and select “Page Properties.” In the window that opens, under the “Tab Order” tab, you can select “Use Document Structure.” This will instruct screen readers to use the tags to determine the order of the document. Note: Make sure you have fixed the tags already before setting tab order.

Resources to Consider