ARIA in HTML

bugsfork meW3C2015-03-17 (commit log)

Abstract

This specification defines the web developer rules (author conformance requirements) for the use of [wai-aria-1.1] attributes on [HTML51] elements. It also defines requirements for Conformance Checking tools.

Table of Contents

This is a draft document and its contents are subject to change without notice.

1. Web developer requirements for use of ARIA in HTML

Web developers MAY use the ARIA role and aria-* attributes on HTML elements, in accordance with the requirements described in [wai-aria-1.1], except where these conflict with the strong native semantics or are equal to the default implicit ARIA semantics of a given HTML element. These constraints, are intended to prevent developers from making assistive technology products report nonsensical user interface information (UI) that does not represent the actual UI of the document.

Web developers MUST NOT use the ARIA role and aria-* attributes in a manner that conflicts with the semantics described in the Document conformance requirements for use of ARIA attributes in HTML table. Web developers SHOULD NOT set the ARIA role and aria-* attributes to values that match the default implicit ARIA semantics defined in the table.

The following uses a role=heading on a button element. This is not allowed, because the button element has default characteristics that conflict with the heading role.
      <button role="heading">search</button>
      

If you check this file using a HTML5 conformance checker an error will be displayed.

non conforming ARIA use example:

Default Implicit ARIA Semantics

The following table describes the default implicit ARIA semantics that apply to HTML elements as defined in the HTML Accessibility API Mappings specification. Each language feature (element or attribute) in a cell in the first column implies the ARIA semantics (any role, states, and properties) given in the cell in the second column of the same row.

Note

Setting an ARIA role and/or aria-* attribute that matches the default implicit ARIA semantics is unnecessary and is NOT RECOMMENDED as these properties are already set by the browser.

2. Document conformance requirements for use of ARIA attributes in HTML

Rules of ARIA attributes usage by HTML language feature
HTML language feature Default Implicit ARIA semantics - SHOULD NOT be used ARIA roles, states and properties which MAY be used
a element with a href role=link

Roles: button, checkbox, menuitem, menuitemcheckbox, menuitemradio, tab, or treeitem

global aria-* attributes and any aria-* attributes applicable to the allowed roles

a element without a href NONE

Any role

global aria-* attributes and any aria-* attributes applicable allowed roles

address NONE

Role: contentinfo
global aria-* attributes

area with a href role=link

Any aria-* attributes applicable to the link role. Any global aria-* attributes

article role=article

Roles: presentation, document, application, or main.
global aria-* attributes and any aria-* attributes applicable to the allowed roles

aside role=complementary

Roles: note or search.

global aria-* attributes and any aria-* attributes applicable to the allowed roles

audio NONE

Role: application
global aria-* attributes and any aria-* attributes applicable to the application role.

base NONE No role or aria* attributes
body role=document global aria-* attributes
button role=button

Roles: link, menuitem, menuitemcheckbox, menuitemradio, radio.
global aria-* attributes and any aria-* attributes applicable to the allowed roles

button type="menu" role=button

Roles: link, menuitem, menuitemcheckbox, menuitemradio, radio.
global aria-* attributes and any aria-* attributes applicable to the allowed roles

caption NONE global aria-* attributes

col, colgroup

NONE No role or aria* attributes
datalist role=listbox

global aria-* attributes and any aria-* attributes applicable to the listbox role.

dd, dt NONE global aria-* attributes
details role=group global aria-* attributes and any aria-* attributes applicable to the group role.
dialog role=dialog

global aria-* attributes and any aria-* attributes applicable to the dialog role.

div No role

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

dl role=list

global aria-* attributes

embed NONE

Role: application, document, presentation or img

global aria-* attributes and any aria-* attributes applicable to the allowed roles

figure NONE

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

form role=form

global aria-* attributes

grouping content elements not listed elsewhere:

p, pre, blockquote

NONE

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

h1 to h6 element role=heading, with the aria-level = positive integer global aria-* attributes
hr role=separator global aria-* attributes and any aria-* attributes applicable to the separator role.
html NONE No role or aria* attributes
iframe NONE

Role: application, document, or img

globalaria-* attributes and any aria-* attributes applicable to the allowed roles

iframe (seamless) NONE

Role: application, document, or img

global aria-* attributes and any aria-* attributes applicable to the allowed roles

img with alt="" NONE No role or aria* attributes
img with alt="some text" role=img

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

input type= button role=button

Role: link, menuitem, menuitemcheckbox, menuitemradio, radio

global aria-* attributes and any aria-* attributes applicable to the allowed roles

input type= checkbox

role=checkbox

No role

global aria-* attributes

input type = color NONE

No role

global aria-* attributes

input type = date NONE

No role

global aria-* attributes

input type = datetime NONE

No role

global aria-* attributes

input type = email with no list attribute role=textbox

global aria-* attributes and any aria-* attributes applicable to the textbox role

input type = file NONE

No role

global aria-* attributes

input type = hidden NONE No role or aria* attributes
input type= image role=button

Role: link, menuitem, menuitemcheckbox, menuitemradio, radio

global aria-* attributes and any aria-* attributes applicable to the allowed roles

input type = month NONE

No role

global aria-* attributes

input type = number role=spinbutton

global aria-* attributes and any aria-* attributes applicable to the spinbutton role.

input type = password role=textbox

No role

global aria-* attributes

input type = radio role=radio

role: menuitemradio

global aria-* attributes and any aria-* attributes applicable to the menuitemradio role.

input type = range role=slider

global aria-* attributes and any aria-* attributes applicable to the slider role.

input type= reset role=button

No role

global aria-* attributes and any aria-* attributes applicable to the button role.

input type = search, with no list attribute role=textbox

No role

global aria-* attributes

input type = submit role=button

No role

global aria-* attributes and any aria-* attributes applicable to the button role.

input type = tel with no list attribute role=textbox

No role

global aria-* attributes

input type = text with no list attribute role=textbox

No role

global aria-* attributes

input type = text, search, tel, url, or email with a list attribute role=combobox

No role

global aria-* attributes and any aria-* attributes applicable to the combobox role.

input type= time NONE

No role

global aria-* attributes

input type = url with no list attribute role=textbox

No role

global aria-* attributes

input type = week NONE

No role

global aria-* attributes

ins and del

NONE

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

keygen NONE

No role

global aria-* attributes

label NONE

No role

global aria-* attributes

li element whose parent is an ol or ul role=listitem

Role: listitem, menuitem, menuitemcheckbox, menuitemradio, option, separator, tab, or treeitem

link element with a href role=link No role or aria* attributes
main role=main

No role

global aria-* attributes

map NONE No role or aria* attributes
math NONE

No role

global aria-* attributes

menu type = toolbar role=toolbar

global aria-* attributes and any aria-* attributes applicable to the toolbar role.

menuitem type = command role=menuitem

global aria-* attributes and an y aria-* attributes applicable to the menuitem role.

menuitem type = checkbox role=menuitemcheckbox

global aria-* attributes and any aria-* attributes applicable to the menuitemcheckbox role.

menuitem type = radio role=menuitemradio

global aria-* attributes and any aria-* attributes applicable to the menuitemradio role.

meta NONE No role or aria* attributes
meter role=progressbar global aria-* attributes
nav role=navigation global aria-* attributes
noscript NONE No role or aria* attributes
object NONE

Role: application, document, or img

global aria-* attributes and any aria-* attributes applicable to the allowed roles

ol role=list

Role: directory, group, listbox, menu, menubar, tablist, toolbar or tree

global aria-* attributes and any aria-* attributes applicable to the allowed roles

optgroup NONE global aria-* attributes
option element that is in a list of options or that represents a suggestion in a datalist role=option

global aria-* attributes

output NONE

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

param NONE No role or aria* attributes
picture NONE No role or aria* attributes
progress role=progressbar

global aria-* attributes and any aria-* attributes applicable to the progressbar role.

script NONE No role or aria* attributes
section role=region

Role: alert, alertdialog, application, contentinfo, dialog, document, log, marquee, search, or status

global aria-* attributes and any aria-* attributes applicable to the allowed roles

select role=listbox

global aria-* attributes

source NONE No role or aria* attributes
span NONE

Any role

global aria-* attributes and any aria-* attributes applicable to the allowed roles

style NONE No role or aria* attributes
SVG NONE

Role: application, document, or img

global aria-* attributes and any aria-* attributes applicable to the allowed roles

summary role=button

Role: button with aria-expanded="true" if the parent (details) element's open attribute is present, aria-expanded="false" otherwise.

global aria-* attributes and any aria-* attributes applicable to the button role.

table NONE

Role: any

global aria-* attributes and any aria-* attributes applicable to the allowed roles

template NONE No role or aria* attributes
textarea role=textbox

global aria-* attributes

tbody, thead, tfoot

role=rowgroup

Role: any

global aria-* attributes

title NONE No role or aria* attributes
td NONE

Role: any

global aria-* attributes and any aria-* attributes applicable to the allowed roles

Text level semantic elements not listed elsewhere:

em, strong, small, s, cite, q, dfn, abbr, time, code, var, samp, kbd, sub and sup, i, b, u, mark , ruby, rt, rp, bdi, bdo, br, wbr

NONE Role: any

global aria-* attributes and any aria-* attributes applicable to the allowed roles

th role=columnheader

Role: any

global aria-* attributes and any aria-* attributes applicable to the allowed roles

tr

NONE

Role: any

global aria-* attributes and any aria-* attributes applicable to the allowed roles

track NONE No role or aria* attributes
ul role=list

Role: directory, group, listbox, menu, menubar, tablist, toolbar, tree, presentation

global aria-* attributes and any aria-* attributes applicable to the allowed roles

video NONE

Role: application

global aria-* attributes and any aria-* attributes applicable to the application role.

Element with a disabled attribute aria-disabled="true"

Use the disabled attribute on any element that is allowed the disabled attribute in HTML5.

Only use the aria-disabled attribute for elements that are not allowed to have a disabled attribute in HTML5

Element with a required attribute aria-required="true"

Use the aria-required attribute on any element that is allowed the required attribute in HTML5.

MAY also be used for elements that have an attached ARIA role which allows the aria-required attribute.

Element with a readonly attribute aria-readonly="true"

Use the readonly attribute on any element that is allowed the readonly attribute in HTML5.

Only use the aria-readonly attribute for elements that are not allowed to have a readonly attribute in HTML5

Element with a hidden attribute aria-hidden="true"  
Element that is a candidate for constraint validation but that does not satisfy its constraints aria-invalid="true"

Only use the aria-invalid attribute for elements that are not allowed to have a readonly attribute in HTML5

The elements marked with NONE, in the second column of the table do not have any default implicit ARIA semantics, but they do have meaning and this meaning may be represented in roles, states and properties not provided by ARIA, and exposed to users of assitive technology via accessibility APIs. It is therefore recommended that web developers add a role attribute to a semantically neutral element such as a div or span, rather than overriding the semantics of the listed elements.

Note

Authors are encouraged to make use of the following documents for guidance on using ARIA in HTML beyond that which is provided here:

  • Using WAI-ARIA in HTML - A practical guide for developers on how to to add accessibility information to HTML elements using the Accessible Rich Internet Applications specification [wai-aria].
  • WAI-ARIA 1.0 Authoring Practices - An author's guide to understanding and implementing Accessible Rich Internet Applications.

These features can be used to make accessibility tools render content to their users in more useful ways. For example, ASCII art, which is really an image, appears to be text, and in the absence of appropriate annotations would end up being rendered by screen readers as a very painful reading of lots of punctuation. Using the features described in this section, one can instead make the ATs skip the ASCII art and just read the caption:

<figure role="img" aria-labelledby="fish-caption"
   <pre>
   o           .'`/
     '      /  (
   O    .-'` ` `'-._      .')
      _/ (o)        '.  .' /
      )       )))     ><  <
      `\  |_\      _.'  '. \
        '-._  _ .-'       '.)
    jgs     `\__\
   </pre>
   <figcaption id="fish-caption">
    Joan G. Stark, "<cite>fish</cite>".
    October 1997. ASCII on electrons. 28×8.
   </figcaption>
   </figure>
   

3. Allowed ARIA roles, states and properties

This section is non-normative.

Note

The following table provides an informative reference to the ARIA roles, states and properties permitted for use in HTML. All ARIA roles, states and properties are normatively defined in the [wai-aria] specification. Links to ARIA roles, states and properties in the table reference the normative [wai-aria] definitions.

ARIA Roles, States and Properties
Role Description Required Properties Supported Properties
any ARIA global states and properties can be used on any HTML element. none
alert A message with important, and usually time-sensitive, information. See related alertdialog and status. none
alertdialog A type of dialog that contains an alert message, where initial focus goes to an element within the dialog. See related alert dialog. none
application A region declared as a web application, as opposed to a web document. none
article A section of a page that consists of a composition that forms an independent part of a document, page, or site. none
banner A region that contains mostly site-oriented content, rather than page-specific content. none
button An input that allows for user-triggered actions when clicked or pressed. See related link. none
checkbox A checkable input that has three possible values: true, false, or mixed.
columnheader A cell containing header information for a column. none
combobox A presentation of a select; usually similar to a textbox where users can type ahead to select an option, or type to enter arbitrary text as a new item in the list. See related listbox.
complementary A supporting section of the document, designed to be complementary to the main content at a similar level in the DOM hierarchy, but remains meaningful when separated from the main content. none
contentinfo A large perceivable region that contains information about the parent document. none
definition A definition of a term or concept. none
dialog A dialog is an application window that is designed to interrupt the current processing of an application in order to prompt the user to enter information or require a response. See related alertdialog. none
directory A list of references to members of a group, such as a static table of contents. none
document A region containing related information that is declared as document content, as opposed to a web application. none
form A landmark region that contains a collection of items and objects that, as a whole, combine to create a form. See related search. none
grid A grid is an interactive control which contains cells of tabular data arranged in rows and columns, like a table. none
gridcell A cell in a grid or treegrid. none
group A set of user interface objects which are not intended to be included in a page summary or table of contents by assistive technologies. none
heading A heading for a section of the page. none
img A container for a collection of elements that form an image. none
An interactive reference to an internal or external resource that, when activated, causes the user agent to navigate to that resource. See related button. none
list A group of non-interactive list items. See related listbox. none
listbox A widget that allows the user to select one or more items from a list of choices. See related combobox and list. none
listitem A single item in a list or directory. none
log A type of live region where new information is added in meaningful order and old information may disappear. See related marquee. none
main The main content of a document. none
marquee A type of live region where non-essential information changes frequently. See related log. none
math Content that represents a mathematical expression. none
menu A type of widget that offers a list of choices to the user. none
menubar A presentation of menu that usually remains visible and is usually presented horizontally. none
menuitem An option in a group of choices contained by a menu or menubar. none
menuitemcheckbox A checkable menuitem that has three possible values: true, false, or mixed.
menuitemradio A checkable menuitem in a group of menuitemradio roles, only one of which can be checked at a time.
navigation A collection of navigational elements (usually links) for navigating the document or related documents. none
note A section whose content is parenthetic or ancillary to the main content of the resource. none
option A selectable item in a select list. none
presentation An element whose implicit native role semantics will not be mapped to the accessibility API. none
progressbar An element that displays the progress status for tasks that take a long time. none
radio A checkable input in a group of radio roles, only one of which can be checked at a time.
radiogroup A group of radio buttons. none
region A large perceivable section of a web page or document, that the author feels is important enough to be included in a page summary or table of contents, for example, an area of the page containing live sporting event statistics. none
row A row of cells in a grid. none
rowgroup A group containing one or more row elements in a grid. none
rowheader A cell containing header information for a row in a grid. none
scrollbar A graphical object that controls the scrolling of content within a viewing area, regardless of whether the content is fully displayed within the viewing area.
A landmark region that contains a collection of items and objects that, as a whole, combine to create a search facility. See related form . none
separator A divider that separates and distinguishes sections of content or groups of menuitems.
  • none
slider A user input where the user selects a value from within a given range.
spinbutton A form of range that expects the user to select from among discrete choices.
status A container whose content is advisory information for the user but is not important enough to justify an alert, often but not necessarily presented as a status bar. See related alert. none
tab A grouping label providing a mechanism for selecting the tab content that is to be rendered to the user. none
tablist A list of tab elements, which are references to tabpanel elements. none
tabpanel A container for the resources associated with a tab, where each tab is contained in a tablist. none
textbox Input that allows free-form text as its value. none
timer A type of live region containing a numerical counter which indicates an amount of elapsed time from a start point, or the time remaining until an end point. none
toolbar A collection of commonly used function buttons represented in compact visual form. none
tooltip A contextual popup that displays a description for an element. none
tree A type of list that may contain sub-level nested groups that can be collapsed and expanded. none
treegrid A grid whose rows can be expanded and collapsed in the same manner as for a tree. none
treeitem An option item of a tree. This is an element within a tree that may be expanded or collapsed if it contains a sub-level group of treeitems. none

4. Requirements for implementers

Conformance Checker implementers

Conformance checkers that claim support for checking of ARIA in HTML, MUST implement checks for the document conformance requirements for use of the ARIA role and aria-* attributes on HTML elements as defined in this specification.

Documents MUST NOT use any role values with elements in the Document conformance requirements for use of ARIA attributes in HTML table, other than the corresponding role value (if any) as listed for that element in the third column, other than those indicated in the second column, which SHOULD NOT be used.

Conformance checkers are encouraged to phrase errors such that developers are encouraged to use more appropriate elements rather than remove accessibility information. For example, if an a element is marked as having the button role, a conformance checker could say "Use a more appropriate element to represent a button, for example a button element or an input element" rather than "The button role should not be used with a elements".

5. Conformance Requirements

All diagrams, examples, and notes in this specification are non-normative, as are all sections explicitly marked non-normative. Everything else in this specification is normative.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in the normative parts of this document are to be interpreted as described in RFC2119. The key word "OPTIONALLY" in the normative parts of this document is to be interpreted with the same normative meaning as "MAY" and "OPTIONAL". For readability, these words do not appear in all uppercase letters in this specification. [RFC2119]]

A. References

A.1 Normative references

[HTML51]
Ian Hickson; Robin Berjon; Steve Faulkner; Travis Leithead; Erika Doyle Navara; Edward O'Connor; Tab Atkins Jr.; Simon Pieters; Yoav Weiss; Marcos Caceres; Mathew Marquis. HTML 5.1. 17 March 2015. W3C Working Draft. URL: http://www.w3.org/TR/html51/
[RFC2119]
S. Bradner. Key words for use in RFCs to Indicate Requirement Levels. March 1997. Best Current Practice. URL: https://tools.ietf.org/html/rfc2119
[wai-aria]
James Craig; Michael Cooper et al. Accessible Rich Internet Applications (WAI-ARIA) 1.0. 20 March 2014. W3C Recommendation. URL: http://www.w3.org/TR/wai-aria/
[wai-aria-1.1]
James Craig; Michael Cooper; Shane McCarron. Accessible Rich Internet Applications (WAI-ARIA) 1.1. 11 December 2014. W3C Working Draft. URL: http://www.w3.org/TR/wai-aria-1.1/