What are PDF tags?

Tags are the basis for accessibility within a PDF. Without proper tags there is no accessibility. Tag elements provide semantic information for screen readers, control the reading order, and other important functions. An important first step is to determine if your PDF has tags. Review this post to find out if your document has tags.

Why do PDF tags matter?

Assistive technology will read tags and use them as a method for navigating larger documents. A tagged PDF is essential for those with visual disabilities and anyone who is using assistive technology like JAWS or NVDA.

PDF tags make it possible to identify content like headings, lists, links, tables, forms, and other important features. Not all programs can export a tagged PDF – so make sure you are using the right tools!

Sample screenshot of tags panel

Sample screenshot of the tags panel

Video overview of PDF Tags

Tag Relationships

Tags come in a pair and can sometimes be referred to as a Parent-Child relationships. In the example below the Figure tag is the parent tag and image container is the Child tag.

Every parent tag will have a child tag. This is useful for moving tags around in the tags panel.

The PDF Tags breakdown

If a tag is not properly categorized it will fail accessibility checks and be confusing to its users. Adding tags does not change the visual appearance of the document; it provides invisible layer of formatting within the document that works with screen readers. PDF tags also allows the content to reflow seamlessly on devices with smaller screens, like smartphones and tablets. Here is a brief explanation of what each tag represents:

<P>

The P tag is the most basic and universal tag. This tag is used as body text.

<H1> <H2> <H3> <H4> <H5> <H6>

These are heading tags. Most documents will have a single H1 tag, but larger documents could contain more. Modern assistive technology can recognize up to six heaving levels. Always use headings in order. Think of them like an outline.

  1. The Parent Tag <H1>
  2. The child tag (container)
  3. The content the tag is referencing (content on page)
The Parent Tag <H1>
The child tag (container)
The content the tag is referencing (content on page)

pdf tags

<L> <LI> <Lbl> <LBody>

List elements contain a specific structure. These tags represent the structure of accessible lists. Some accessibility guidelines require the use of Lbl and other guidelines do not.

  1. List Parent Tag <L>
  2. List Item Child Tag <LI>
  3. Label <Lbl>
  4. List Body child Tag <LBody>
  5. Contents of First list item
  6. List item content on page
List Parent Tag <L>
List Item Child Tag <LI>
Label <Lbl>
List Body child Tag <LBody>
Contents of First list item
List item content on page


pdf tags

<Figure>

The figure tag represents any and all images. At this time the figure tag is used for all graphics within a PDF.

  1. <Figure> is a parent tag
  2. The Image is a child tag (container)
  3. The image as content on page
<Figure> is a parent tag

The Image is a child tag (container)

The image as content on page

<Table> <TR> <TH> <TD>

Reading plain text is an easy task for assistive technologies. A table of data presents a complex more task. Proper PDF tag structure makes this possible by identifying essential information including the number of rows and columns as well as column (or row) headers, and which heading each data entry corresponds to. The more complex a table is, the more significant the challenge to tag it correctly.

  1. Table Parent Tag <Table>
  2. Table Row Child tag <TR>
  3. Table Header Cell <TH>
  4. Table Data Cell <TD>
  5. Table on Page
Table Parent Tag <Table>
Table Row Child tag <TR>
Table Header Cell <TH>
Table Data Cell <TD>
Table on Page

<Link>, Link – OBJR

Every link tag needs a Link-OBJR tag.

  1. Parent tag <P>
  2. Link Tag <Link>
  3. Link Reference Object
  4. The link Text on screen
  5. Content on page
Parent tag <P>
Link Tag <Link>
Link Reference Object 
The link Text on screen
Content on page

<Reference> & <Note>

Reference and Note tags are up for interpretation but are commonly used within PDFs to “visually” break content apart.

Reading Order

An accessible PDF provides the instructions to the assistive technologies such as screen readers to read the content properly and in the correct order. The tag order within the tag tree will determine the reading order of the document. For documents without this logical structure, the best case would be that assistive technologies would guess at the correct order that the content should be presented in. In worst cases, the content would be completely unable to be read. The outcome is that the content becomes useless to the user.

How do I apply tags to a document?

There are multiple methods to apply tags to a document. The most common methods are:

Advanced Tag Breakdown

The following is a detailed breakdown of available tag structure within a pdf. It has been adapted from https://accessible-pdf.info/basics/general/overview-of-the-pdf-tags

Grouping elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
DocumentRepresents a complete documentGrouping elements, Block-level structure elements
PartDivision of a larger document into smaller, associated partsDocumentArtSectDivBlockQuoteCaptionTOCIndex
ArtParts of content which together are conclusive, i.e. an article or part of a documentDocumentPartSectDivBlockQuoteSectDivBlockQuoteCaptionTOCIndex
SectGrouped related content parts, for example several paragraphs, which can be combined into a groupDocumentPartArtSectDivBlockQuoteArtSectDivBlockQuoteCaptionTOCIndex
DivGeneric group element without semantic meaningDocumentPartArtSectDivBlockQuoteArtSectDivBlockQuoteCaptionTOCIndex
BlockQuoteOne or more paragraphs that originate from another author, in other words, that have been quotedDocumentPartArtSectDivArtSectDivCaption
CaptionA caption to describe for example a picture or a tableDocumentPartArtSectDivBlockQuoteTableLSectDivBlockQuote
TOCContainer for table of contents entries. Can be used either as a flat hierarchy (all contained TOCI on one level) or as a complex hierarchy (TOC within a TOCI as a subgroup). Can be contained multiple times in a document, since it can also be used for image or table directories.DocumentPartArtSectDivTOCI
TOCIEntry within a table of contents (TOC).TOCTOCPLblReference
IndexContainer for a subject indexDocumentPartArtSectDivL

Block-level structure elements

Paragraph elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
POrdinary paragraphDocumentPartArtSectDivBlockQuoteCaptionTOCIInline-level structure elements
H1H2H3H4H5H6Hierarchical headings on levels 1 to 6DocumentPartArtSectDivBlockQuoteInline-level structure elements

List elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
LList container; groups together all list elements that belong togetherDocumentPartArtSectDivBlockQuoteIndexLICaption
LIContainer of a list entry; can contain an L to create multi-level listsLLblLBodyL
LblComes from the term “label” and represents the numbering or bullet character within a list. It’s not actually a block-level structure element and can also be used in other elements such as TOCI or Caption.LI
LBodyContains the contents of a list entryLIInline-level structure elements

Table elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
TableTable container; combines all related table elementsDocumentPartArtSectDivBlockQuoteTRCaptionTHeadTBodyTFoot
TRGroups a table rowTableTHeadTBodyTFootTHTD
THTable heading cell; describes the meaning either at horizontal (line) or vertical (column) levelTRInline-level structure elements
TDOrdinary table data cellsTRInline-level structure elements
THeadA group of table rows (TR) to mark them as table header; can be used optionallyTableTR
TBodyA group of table rows (TR) to mark them as table content; can be used optionallyTableTR
TFootA group of table rows (TR) to mark them as table footer; can be used optionallyTableTR

Inline-level structure elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
SpanGeneric container without semantic meaning; is used, among other things, for visual markups, language changes or for adding ActualText (e.g. for ignoring hyphens)PH1H6LBodyTDQuoteNote
QuoteUsed like BlockQuote for quoted content; however, Quote is used at line levelPH1H6LBodyTDSpan
NoteFootnote or endnote text (not the reference character in the body text). The footer/end-note character within Note and Reference will be placed in a Lbl.PH1H6LBodyTDLblPSpan
ReferenceRefers to another place in the document, e.g. footnote or directory entryPH1H6LBodyTDLbl
CodeMarking of programming languagePH1H6LBodyTD
LinkLink to a web page or to a place within the documentPH1H6LBodyTD
AnnotAnnotations that are not a link or a widget (form field), like comments and videos.PH1H6LBodyTD

Illustration graphic elements

PDF tagSemantic meaningPossible and semantically meaningful parent elementsPossible and semantically meaningful child elements
FigurePhoto or graphicDocumentPartArtSectDivBlockQuotePLBodyTD
FormulaMathematical formulaDocumentPartArtSectDivBlockQuotePH1H6LBodyTD
FormForm elementDocumentPartArtSectDivPTD

Need more PDF Training?

Scan and OCR a PDF in Adobe Acrobat Pro DC

Do you ever have an image in your PDF that you need to OCR and make text? Adobe Acrobat has a feature called Scan and OCR which can do just that. This is useful for when you have a scanned image or poor-quality PDF.

Best practice

Try to avoid using images of text as this is a direct violation of accessibility guidelines. This is why the Scan and OCR feature is useful.

Video Overview of how to use the Scan and OCR feature in Adobe Acrobat

Text Overview of how to use the Scan and OCR feature

  1. Select the scan and ocr tool
  2. Select recognize text in this file
  3. Select recognize text
Select the scan and ocr tool

Select recognize text in this file

Select recognize text

How do I test to make sure that it worked?

The best method to ensure that your Scan and OCR worked is to try and copy and paste the text into another program. This will tell you that the OCR took place and will allow you to check for accuracy.

Are there any better OCR programs?

Adobe Acrobats OCR tool is not the best when it comes to accuracy. If you are using OCR for textbooks or high quantities of documents, id refer you to check out Abbyy FineReader. Lucky for you – I have a bunch of videos about this program too.

Need additional help on accessible PDFs? Review the links below

Order 508 documents

Subscribe to The Accessibility Guy posts

* indicates required

How do I convert my Word document to PDF?

Im not sure I could keep count of the number of times I have been asked this question so here is a whole post dedicated to the topic!

Do not use the print to pdf function in MS Word. This will overwrite all of your hard work that you did in MS Word.

The Accessibility Guy

If you properly format your word document – you can export an almost perfect PDF file that will be close to passing accessibility requirements. By making a word document accessible, you can cut the time to remediate a PDF by more than 90%. Need some guidance on how to make Word documents accessible? The image below is a link to the Microsoft Word accessibility page.

Video Overview of how to convert from Word to PDF and retain the structure

Text Overview for how to set settings for export from Word to PDF

Step 1

Ensure that your word document is fully accessible. This page will walk you through all the steps required for making a word document accessible.

Step 2

Select File > Export > Create XPS / PDF Document

File export create pdf/xps

Step 3

Select the options button to adjust settings before selecting publish. These options will ensure that you are exporting a tagged pdf.

select options

Step 4

Adjust the options to reflect the following:

  • Page range set to all
  • Publish what set to Document
  • Include non-printing information has all three checkboxes selected
Page range set to all

Publish what set to Document

Include non-printing information has all three checkboxes selected

Now validate

Open up your PDF and ensure there are tags in the document.

That’s it!

Now you can begin making your PDF document accessible which is much easier if starting with a word document.

Order 508 documents

Subscribe to The Accessibility Guy posts

* indicates required

Does my PDF have tags?

The majority of accessibility occurs in the tags panel but how do you know if your PDF has tags in it?

Important Note: You will need Adobe Acrobat Pro to determine if your document has tags in it. Tags provide the foundation for accessibility and PDFs. If your document is not tagged, it will not be read properly by screen readers and assistive technology.

Does my PDF have tags Video Overview

How to check if your PDF has tags?

There are a couple of ways to view if your PDF has tags in it.

Option 1

  1. Open a document in adobe acrobat pro
  2. Right click the far left side of the menu
  3. Select tag
Open a document in adobe acrobat pro
Right click the far left side of the menu
Select tag

Option 2

  1. Select View
  2. Select Show / Hide
  3. Select Navigational Panels
  4. Select Tags
Select View
Select Show / Hide
Select Navigational Panels
Select Tags

Your document will either say No Tags or you will see a list of tags available.

Document with no tags

This means that the document is not going to be read properly by assistive technology.

Sample PDF with no tags available

Document with tags

This example provides a tagged PDF with information that is passed onto assistive technology.

sample document with tags

Subscribe to The Accessibility Guy posts

* indicates required