Standard PDF Tag Types

Below is a list of the standard set of tag types defined by the PDF format. These standard types are designed to help accessibility software like screen readers understand the document structure to present the information to users with disabilities in an understandable way.

Note: Xodo PDF Studio only supports creating or editing the standard types defined by the PDF standards, however additional applications can choose to set custom tag values not part of the standard types. In this case Xodo PDF Studio will just display the name of the custom tag value set by the authoring application.


Container elements are the highest level elements in the tag structure

Document - Root element of a document’s tag tree.

Part - Large division of a document; may group smaller units of content together, such as division, article, or section elements.

Division - Generic block element or group of elements.

Article - Self-contained body of text considered to be a single narrative.

Section - General container element type that is usually a component of a Part or Article element

Heading and Paragraph

Heading and paragraph are block elements that include specific level heading and paragraph tags.

H1 to H6 - The title or heading of a section within the text content

P - A distinct section of a piece of writing, usually dealing with a single theme and indicated by a new line or indentation

Label and List

Label and list elements are used to mark content such as a list or bulleted items

List - A group of similar items that are related to each other.

List Item - A single item of a list element, may have a label element (optional) and a list body element is required as a child

Label - A marker such as a bullet, name or number that identifies an element from others in the list

List Item Body - Contains the description of the list item

Special Text

Special text elements mark content that is not considered a heading or paragraph

Block Quote - A large portion of text referencing work from another author

Caption - Text that is used to describe a table or a figure on the page

Index - A list of items, typically at the end of a document, that list the locations of specific keywords within the document

Table of Contents- A list of items, sometimes hierarchical, that contain page numbers to locate that specific item in the document

Table of Contents Item - Specific item found in the table of contents element


Table elements define a section of content organized into rows and columns

Table - Data like text, images, etc. arrented into rows and columns of cells.

Table Header - A cell in a data table that contains header label describing the contents of the column

Table Row - A single row of cell elements within a table

Table Data Cell - An element stored within a single Data cell within at table


Inline-level elements identify a span of text that has specific formatting or behavior. They are differentiated from block-level elements. Inline-level elements may be contained in or contain block-level elements.

Bibliography Entry - Text information referring the user to where the cited text can be found

Quote - A portion of text referencing work from another author, different from a block quote in that it is a single string of text found inline with other text.

Span - An inline segment of text that is formatted differently then the surrounding text, usually to provide emphasis such as Bold or Italic.

Special inline

Similar to inline-level elements, special inline-level elements describe an inline portion of text that has special formatting or behavior.

Code - Text used for computer programming language

Figure - An image or graphic that is referenced by the text

Form - A editable PDF field used to complete a form

Formula - A scientific or mathematical formula element

Link - Hyperlink element that when clicked can navigate a user to a website or location within the current or different PDF file

Note - Additional text or information, such as an endnote or footnote, that is referred to in some previous text

Reference - A text citation in reference to data found elsewhere in the document