Overview of the PDF tags

The tags listed below correspond to the ISO standard PDF 1.7. In 2018 the newer standard PDF 2.0 has been published. In this standard, some of the tags described here have been removed and new ones have been added. Since the standard is not yet widely used and a revision of the PDF/UA standard is still open, this overview still corresponds to PDF 1.7.

Not included in the overview are the PDF tags

  • NonStruct (Grouping element)
  • Private (Grouping element)
  • H (Block-level structure element)
  • BibEntry (Inline-level structure element)
  • Ruby, RB, RT, RP, Warichu, WT, WP (Inline-level structure element)

because they are not recommended or not relevant for use.

It is obvious that grouping elements basically contain block elements and block elements basically contain inline elements. The standard does not always clearly specify which constellations are possible. The illustrative elements can function as block or inline elements.

The third and fourth columns of the overview show semantically meaningful combinations. Although the standard allows other constellations, they are not considered semantically meaningful. However, no guarantee is given for completeness.

Grouping elements

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
Document Represents a complete document Grouping elements, Block-level structure elements
Part Division of a larger document into smaller, associated parts Document Art, Sect, Div, BlockQuote, Caption, TOC, Index, Block-level structure elements
Art Parts of content which together are conclusive, i.e. an article or part of a document Document, Part, Sect, Div, BlockQuote Sect, Div, BlockQuote, Caption, TOC, Index, Block-level structure elements
Sect Grouped related content parts, for example several paragraphs, which can be combined into a group Document, Part, Art, Sect, Div, BlockQuote Art, Sect, Div, BlockQuote, Caption, TOC, Index, Block-level structure elements
Div Generic group element without semantic meaning Document, Part, Art, Sect, Div, BlockQuote Art, Sect, Div, BlockQuote, Caption, TOC, Index, Block-level structure elements
BlockQuote One or more paragraphs that originate from another author, in other words, that have been quoted Document, Part, Art, Sect, Div  Art, Sect, Div, Caption, Block-level structure elements
Caption  A caption to describe for example a picture or a table Document, Part, Art, Sect, Div, BlockQuote, Table, L  Sect, Div, BlockQuote, Block-level structure elements
TOC Container 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. Document, Part, Art, Sect, Div TOCI
TOCI Entry within a table of contents (TOC). TOC TOC, P, Lbl, Reference
 Index Container for a subject index Document, Part, Art, Sect, Div  L 

Block-level structure elements

Paragraph elements

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
 P Ordinary paragraph Document, Part, Art, Sect, Div, BlockQuote, Caption, TOCI  Inline-level structure elements 
H1, H2, H3, H4, H5, H6 Hierarchical headings on levels 1 to 6 Document, Part, Art, Sect, Div, BlockQuote  Inline-level structure elements 

List elements

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
 L List container; groups together all list elements that belong together Document, Part, Art, Sect, Div, BlockQuote, Index  LI, Caption 
LI Container of a list entry; can contain an L to create multi-level lists L  Lbl, LBody, L 
Lbl Comes 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  – 
LBody Contains the contents of a list entry LI  Inline-level structure elements 

Tabellenelemente

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
Table Table container; combines all related table elements Document, Part, Art, Sect, Div, BlockQuote   TR, Caption, THead, TBody, TFoot 
TR Groups a table row Table, THead, TBody, TFoot  TH, TD 
TH Table heading cell; describes the meaning either at horizontal (line) or vertical (column) level TR  Inline-level structure elements 
TD Ordinary table data cells TR  Inline-level structure elements 
THead A group of table rows (TR) to mark them as table header; can be used optionally Table TR
TBody A group of table rows (TR) to mark them as table content; can be used optionally Table TR
TFoot A group of table rows (TR) to mark them as table footer; can be used optionally Table TR

Inline-level structure elements

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
Span Generic container without semantic meaning; is used, among other things, for visual markups, language changes or for adding ActualText (e.g. for ignoring hyphens) P, H1H6, LBody, TD, Quote, Note
Quote Used like BlockQuote for quoted content; however, Quote is used at line level P, H1H6, LBody, TD Span
Note Footnote 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. P, H1H6, LBody, TD Lbl, P, Span
Reference Refers to another place in the document, e.g. footnote or directory entry P, H1H6, LBody, TD Lbl
Code Marking of programming language P, H1H6, LBody, TD
Link Link to a web page or to a place within the document P, H1H6, LBody, TD
Annot Annotations that are not a link or a widget (form field), like comments and videos. P, H1H6, LBody, TD

Illustration elements

PDF tag Semantic meaning Possible and semantically meaningful parent elements Possible and semantically meaningful child elements
Figure Photo or graphic Document, Part, Art, Sect, Div, BlockQuote, P, LBody, TD
Formula Mathematical formula Document, Part, Art, Sect, Div, BlockQuote, P, H1H6, LBody, TD
Form Form element Document, Part, Art, Sect, Div, P, TD