The Reading Order tool provides the easiest and quickest way to fix reading order and basic tagging problems. When you select the tool, a dialog box opens that lets you see overlay highlights that show the order of page content. Each highlighted region is numbered and highlighted with gray or colored blocks; the number indicates the region’s placement in the page’s reading order. After you check the reading order of the page, you can correct other, more subtle tagging issues as needed.
The Reading Order tool is intended for repairing PDFs that were tagged using Acrobat, not for repairing PDFs that were tagged during conversion from an authoring application. Whenever possible, return to the source file and add accessibility features in the authoring application. Repairing the original file ensures that you don’t have to repeatedly touch up future iterations of the PDF in Acrobat.
You can use the Reading Order tool to perform the following accessibility tasks:
Visually check, and then repair, the reading order of page content
Tag fillable form fields and their labels
Add alternate text to figures and descriptions to form fields
Fix the tagging of simple tables, and prepare complex tables for more advanced manipulation in the logical structure tree
Remove nonessential content, such as ornamental page borders, from the logical structure tree
To perform advanced reading order and tagging tasks, such as fixing complex tables, removing obsolete tags, and adding alternate text to links, use the Tags panel. For more information, see Edit tags with the Tags panel.
- Save the document (or a copy of it) before you use the Reading Order tool as undo-redo is not supported for all operations. For more information, see Undo or redo the tag changes done using the Reading Order tool.
- Choose View > Page Display > Single Page View, when using the Reading Order tool. When you click the Clear Page Structure button, Acrobat clears tags from all visible pages, even pages that are only partially visible.
- Choose Tools > Accessibility, and then choose Reading Order in the right pane. The Reading Order tool's dialog box is displayed.
You can select Reading Order options from the dialog box, from the pop-up menu that appears when you right-click a highlighted region, or from the options menu in the Order panel. The Reading Order tool includes the following options:
Tags the selection as a figure. Text contained within a figure tag is defined as part of the image and screen readers don’t read it.
Tags a selected figure and caption as a single tag. Any text contained in the tag is defined as a caption. Useful for tagging photos and captions and preventing caption text from being incorrectly added to adjacent text blocks. Figures may require alternate text.
Heading 1, Heading 2, Heading 3, Heading 4, Heading 5, Heading 6
Tags the selection as a first, second, third, fourth, fifth, or sixth level heading tag. You can convert heading tags to bookmarks to help users navigate the document.
Tags the selection as a table after the selection is analyzed to determine the location of headings, columns, and rows.
Tags the selection as a table or header cell. Use this option to merge cells that are incorrectly split.
Tags the selection as a formula. Because speech software may handle formula tags differently from normal text, you may want to add a description using alternate text.
Tags the selection as a background element, or artifact, removing the item from the tag tree. That way, it doesn’t appear in the reflowed document and screen readers don’t read it.
Automatically analyzes the selected table into cells and applies the appropriate tags. The table must be tagged as a table before you can use the Table Editor command on it.
Show Page Content Groups
Shows content elements as highlighted areas that contain numbers to indicate the reading order. Specify the highlight color by clicking the color swatch.
Show Table Cells
Highlights the content of individual table cells. Specify the highlight color by clicking the color swatch.
Display Like Elements In A Single Block
Adjacent squares with the same tag type are collapsed into a single, bigger square with the common tag type that encompasses the original square.
Show Tables And Figures
Outlines each table and figure with a crossed-out box. The box also indicates whether the element includes alternate text. Specify the box color by clicking the color swatch.
Clear Page Structure
Removes the tagging structure from the page. Use this option to start over and create a new structure if the existing structure contains too many problems.
Edit Alternate Text
Available in the menu that appears when you right-click a highlighted figure. Allows the user to add or edit a text description about the figure properties that a screen reader or other assistive technology reads.
Edit Form Field Text
Available in the menu that appears when you right-click a form field. Allows the user to add or edit a form field text description that a screen reader or other assistive technology reads.
You can quickly check the reading order of tagged PDFs by using the Reading Order tool. You can also use this tool to add alternate text to images and correct many types of tagging problems that are outlined in the report that Acrobat generates when you add tags to a PDF.
Reading-order problems are readily apparent when you use the Reading Order tool. Each section of contiguous page content appears as a separate highlighted region and is numbered according to its placement in the reading order. Within each region,
You can change the reading order of the highlighted regions by moving an item in the Order panel or by dragging it on the page in the document pane. By reordering highlighted regions on the page, you can make a figure and caption read at the specific point that they are referenced in the text. By changing the order of a highlighted region, you effectively change the reading order of that item without changing the actual appearance of the PDF.
In the Order panel, drag the tag for a highlighted region to the location you want. As you drag, a line appears to show potential locations. After you drag an item to a new location, the highlighted regions are renumbered to show the new reading order. You can select and move multiple, adjacent regions.
You can use the Reading Order tool to create tags in untagged PDFs or to add new tags to an existing structure. However, this manual tagging doesn’t provide the same level of detail to the tagging structure as the Add Tags To Document command, such as paragraphs, bulleted and numbered lists, line breaks, and hyphens. Before you clear the existing structure, make sure that manual tagging is your only recourse.
The undo or redo the reading order changes is supported for all tags except the following:
- Table, Table Editor, and related tags.
- Tag creation and tag changes done using Drag and Select in the Reading Order tool.
The Reading Order tool always displays as few highlighted regions as possible. If content within a highlighted region doesn’t flow properly, you may need to split a region to reorder it. Highlighted regions may also contain adjacent page content that is unrelated or that requires a different tag type. Page content may become orphaned from related elements, particularly if the content doesn’t fit within a rectangular shape. Use the Reading Order tool to add or remove content from a region, or to split a region to reorder the content.
To help readers navigate a document and find the information they need, make sure that headings are tagged with the appropriate level to indicate their hierarchy in the content.
In the Reading Order dialog box, click the button corresponding to the appropriate heading tag (for example, Heading 1, Heading 2).
After applying heading tags, you can convert the headings to bookmarks to improve navigation. For more information, see Add tagged bookmarks.
When tagging a PDF, Acrobat can’t always distinguish between instructive figures and decorative page elements. Items that visually enhance page layout, such as decorative borders, lines, or background elements, can add clutter to the structure layout and should be removed. Therefore, Acrobat may incorrectly tag artifacts or page elements as figure tags. You can remove artifacts and irrelevant page elements from the tag structure by redefining them with the Background/Artifact tag or by deleting their tags. If a tagged image in the document doesn’t contain useful or illustrative information for the user, you can remove the element from the tagging structure so that it isn’t read out loud or reflowed.
You can select an element and define it as a figure by using the Reading Order tool. Once you define it as a figure, you can add alternate text to describe the figure.
You can use the Reading Order tool to identify and correct tagging results for figures. Determine whether figures include or require alternate text necessary to be read correctly with assistive technologies. Ideally, figure tags should identify image content that is meaningful to the document as a whole, such as graphs or illustrative photographs. If background/artifact elements that shouldn’t be read are tagged as figures, redefine them as background/artifact.
Do any of the following:
If a figure isn’t tagged as a figure, select the content region you want, and then click Figure or Figure/Caption in the dialog box.
To remove text that was incorrectly combined with a figure, drag to select the text, and click the Text/Paragraph button in the dialog box.
To include a caption that is grouped with the figure, select the figure and caption, and click the Figure/Caption button in the dialog box.
If you want screen readers to describe graphical elements that illustrate important concepts in a document, you must provide the description using alternate text. Figures aren’t recognized or read by a screen reader unless you add alternate text to the tag properties. If you apply alternate text to text elements, only the description, not the actual text, is read.
Tables pose a special challenge for screen readers because they present textual or numerical data to be easily referenced visually. Content within table cells can be complex and might contain lists, paragraphs, form fields, or another table.
For best results when tagging tables, use the application that you created the document with to add tags when you create the PDF. If a PDF isn’t tagged, you can add tags by using the Add Tags To Document command. Most tables are properly recognized using this command; however, the command may not recognize a table that lacks clear borders, headings, columns, and rows. Use the Reading Order tool to determine if the table has been properly recognized and to correct recognition problems. To add specialized formatting to tables and table cells, use the Tags panel.
You can use the Table Editor to automatically analyze a table into its components and apply the appropriate tags, but you may still need to check and correct some of these tags manually. By viewing table tags, you can determine whether columns, rows, and cells have been correctly identified. Tables that lack well-defined borders and rules are often tagged incorrectly or contain adjacent page elements. You can correct poorly tagged tables by selecting and redefining them; you can split combined cells by creating a tag for each cell.
To correct complex tagging problems for tables, you often must use the Tags panel.
If adding tags to a PDF in Adobe Acrobat results in a tagging structure that is overly complicated or too problematic to fix, you can use the Reading Order tool to remove or replace the current structure. If the document contains mostly text, you can select a page and then remove headings, tables, and other elements to create a cleaner, simpler tagging structure.
Acrobat can retag an already tagged document after you first remove all existing tags from the tree.
This procedure works best in pages that contain a single column of text. If the page contains multiple columns, each column must be selected and tagged individually.