IA² RDF/HTML vocabulary
A dated, mechanically generated vocabulary for current HTML elements, attributes, syntax kinds, content categories, and DOM structure in RDF.
0.1 (2026-07-18 HTML Living Standard snapshot)
source snapshot
HTML content category
conditional category membership
DOM node
HTML document
document type
text node
comment node
HTML element
MathML and SVG namespace elements are a syntax kind recorded for provenance; generated named element classes cover only the HTML namespace.
custom or future element
HTML attribute occurrence
indexed HTML attribute definition
HTML attribute applicability and value context
has child
Associates a document or element with a direct child. Strict-precedence closure derives the remaining children in the same sibling ordering; immediate precedence additionally asserts adjacency.
child of
Inverse of rdfhtml:hasChild and a specialization of ordering-context membership.
ordered children
Links a document or element to one complete RDF list of its direct children. Processors normalize the list to child membership and immediate precedence before validation.
document base IRI
node data
metadata content
flow content
sectioning content
heading content
phrasing content
embedded content
interactive content
form-associated elements
listed elements
submittable elements
resettable elements
autocapitalize-and-autocorrect inheriting elements
labelable elements
palpable content
script-supporting elements
a element
abbr element
address element
area element
article element
aside element
audio element
b element
base element
bdi element
bdo element
blockquote element
body element
br element
button element
canvas element
caption element
cite element
code element
col element
colgroup element
data element
datalist element
dd element
del element
details element
dfn element
dialog element
div element
dl element
dt element
em element
embed element
fieldset element
figcaption element
figure element
footer element
form element
h1 element
h2 element
h3 element
h4 element
h5 element
h6 element
head element
header element
hgroup element
hr element
html element
i element
iframe element
img element
input element
ins element
kbd element
label element
legend element
li element
link element
main element
map element
mark element
menu element
meta element
meter element
nav element
noscript element
object element
ol element
optgroup element
option element
output element
p element
picture element
pre element
progress element
q element
rp element
rt element
ruby element
s element
samp element
script element
search element
section element
select element
selectedcontent element
slot element
small element
source element
span element
strong element
style element
sub element
summary element
sup element
table element
tbody element
td element
template element
textarea element
tfoot element
th element
thead element
time element
title element
tr element
track element
u element
ul element
var element
video element
wbr element
abbr attribute
accept attribute
accept-charset attribute
accesskey attribute
action attribute
allow attribute
allowfullscreen attribute
alpha attribute
alt attribute
as attribute
async attribute
autocapitalize attribute
autocomplete attribute
autocorrect attribute
autofocus attribute
autoplay attribute
blocking attribute
charset attribute
checked attribute
cite attribute
class attribute
closedby attribute
color attribute
colorspace attribute
cols attribute
colspan attribute
command attribute
commandfor attribute
content attribute
contenteditable attribute
controls attribute
coords attribute
crossorigin attribute
data attribute
datetime attribute
decoding attribute
default attribute
defer attribute
dir attribute
dirname attribute
disabled attribute
download attribute
draggable attribute
enctype attribute
enterkeyhint attribute
fetchpriority attribute
for attribute
form attribute
formaction attribute
formenctype attribute
formmethod attribute
formnovalidate attribute
formtarget attribute
headers attribute
headingoffset attribute
headingreset attribute
height attribute
hidden attribute
high attribute
href attribute
hreflang attribute
http-equiv attribute
id attribute
imagesizes attribute
imagesrcset attribute
inert attribute
inputmode attribute
integrity attribute
is attribute
ismap attribute
itemid attribute
itemprop attribute
itemref attribute
itemscope attribute
itemtype attribute
kind attribute
label attribute
lang attribute
list attribute
loading attribute
loop attribute
low attribute
max attribute
maxlength attribute
media attribute
method attribute
min attribute
minlength attribute
multiple attribute
muted attribute
name attribute
nomodule attribute
nonce attribute
novalidate attribute
open attribute
optimum attribute
pattern attribute
ping attribute
placeholder attribute
playsinline attribute
popover attribute
popovertarget attribute
popovertargetaction attribute
poster attribute
preload attribute
readonly attribute
referrerpolicy attribute
rel attribute
required attribute
reversed attribute
rows attribute
rowspan attribute
sandbox attribute
scope attribute
selected attribute
shadowrootclonable attribute
shadowrootcustomelementregistry attribute
shadowrootdelegatesfocus attribute
shadowrootmode attribute
shadowrootserializable attribute
shadowrootslotassignment attribute
shape attribute
size attribute
sizes attribute
slot attribute
span attribute
spellcheck attribute
src attribute
srcdoc attribute
srclang attribute
srcset attribute
start attribute
step attribute
style attribute
tabindex attribute
target attribute
title attribute
translate attribute
type attribute
usemap attribute
value attribute
width attribute
wrap attribute
writingsuggestions attribute
Alternative label to use for the header cell when referencing the cell in other contexts
Set of comma-separated tokens* consisting of valid MIME type strings with no parameters or audio/*, video/*, or image/*
Hint for expected file type in file upload controls
ASCII case-insensitive match for "UTF-8"
Character encodings to use for form submission
Ordered set of unique space-separated tokens, none of which are identical to another, each consisting of one code point in length
Keyboard shortcut to activate or focus element
Valid non-empty URL potentially surrounded by spaces
URL to use for form submission
Permissions policy to be applied to the iframe's contents
Whether to allow the iframe's contents to use requestFullscreen()
Allow the color's alpha component to be set
Replacement text for use when images are not available
Preload destination, for rel="preload"; module preload destination, for rel="modulepreload"
Destination for a preload request (for rel="preload" and rel="modulepreload")
Execute script when available, without blocking while fetching
"on"; "off"; "none"; "sentences"; "words"; "characters"
Recommended autocapitalization behavior (for supported input methods)
Default setting for autofill feature for controls in the form
Hint for form autofill feature
Recommended autocorrection behavior (for supported input methods)
Automatically focus the element when the page is loaded
Hint that the media resource can be started automatically when the page is loaded
Unordered set of unique space-separated tokens*
Whether the element is potentially render-blocking
Character encoding declaration
Whether the control is checked
Valid URL potentially surrounded by spaces
Link to the source of the quotation or more information about the edit
Classes to which the element belongs
Which user actions will close the dialog
Color to use when customizing a site's icon (for rel="mask-icon")
The color space of the serialized color
Valid non-negative integer greater than zero
Maximum number of characters per line
Number of columns that the cell is to span
"toggle-popover"; "show-popover"; "hide-popover"; "close"; "request-close"; "show-modal"; a custom command keyword
Indicates to the targeted element which action to take.
Targets another element to be invoked.
Value of the element
"true"; "false"; "plaintext-only"; the empty string
Whether the element is editable
Show user agent controls
Coordinates for the shape to be created in an image map
"anonymous"; "use-credentials"; the empty string
How the element handles crossorigin requests
Address of the resource
Date and (optionally) time of the change
Valid month string, valid date string, valid yearless date string, valid time string, valid local date and time string, valid time-zone offset string, valid global date and time string, valid week string, valid non-negative integer, or valid duration string
Machine-readable value
Decoding hint to use when processing this image for presentation
Enable the track if no other text track is more suitable
Defer script execution
The text directionality of the element
Name of form control to use for sending the element's directionality in form submission
Whether the form control is disabled
Whether the descendant form controls, except any inside legend, are disabled
Whether the link is disabled
Whether to download the resource instead of navigating to it, and its filename if so
Whether the element is draggable
"application/x-www-form-urlencoded"; "multipart/form-data"; "text/plain"
Entry list encoding type to use for form submission
"enter"; "done"; "go"; "next"; "previous"; "search"; "send"
Hint for selecting an enter key action
Sets the priority for fetches initiated by the element
Associate the label with form control
Unordered set of unique space-separated tokens consisting of IDs*
Specifies controls from which the output was calculated
Associates the element with a form element
Variant to use for form submission
Bypass form control validation for form submission
Navigable for form submission
The header cells for this cell
Valid non-negative integer between 0 and 8
Offsets heading levels for descendants
Prevents a heading offset computation from traversing beyond the element with the attribute
Vertical dimension
"until-found"; "hidden"; the empty string
Whether the element is relevant
Low limit of high range
Address of the hyperlink
Document base URL
Language of the linked resource
"content-type"; "default-style"; "refresh"; "x-ua-compatible"; "content-security-policy"
Pragma directive
The element's ID
Image sizes for different page layouts (for rel="preload")
Comma-separated list of image candidate strings
Images to use in different situations, e.g., high-resolution displays, small monitors, etc. (for rel="preload")
Whether the element is inert.
"none"; "text"; "tel"; "email"; "url"; "numeric"; "decimal"; "search"
Hint for selecting an input modality
Integrity metadata used in Subresource Integrity checks [SRI]
Valid custom element name of a defined customized built-in element
Creates a customized built-in element
Whether the image is a server-side image map
Global identifier for a microdata item
Unordered set of unique space-separated tokens consisting of valid absolute URLs, defined property names, or text*
Property names of a microdata item
Referenced elements
Introduces a microdata item
Unordered set of unique space-separated tokens consisting of valid absolute URLs*
Item types of a microdata item
"subtitles"; "captions"; "descriptions"; "chapters"; "metadata"
The type of text track
User-visible label
Valid BCP 47 language tag or the empty string
Language of the element
List of autocomplete options
Used when determining loading deferral
Whether to loop the media resource
High limit of low range
Maximum value
Upper bound of range
Maximum length of value
Applicable media
Minimum value
Lower bound of range
Minimum length of value
Whether to allow multiple values
Whether to mute the media resource by default
Name of the element to use for form submission and in the form.elements API
Name of group of mutually-exclusive details elements
Name of form to use in the document.forms API
Name of content navigable
Name of image map to reference from the usemap attribute
Metadata name
Name of shadow tree slot
Prevents execution in user agents that support module scripts
Cryptographic nonce used in Content Security Policy checks [CSP]
Whether the details are visible
Whether the dialog box is showing
Optimum value in gauge
Regular expression matching the JavaScript Pattern production
Pattern to be matched by the form control's value
Set of space-separated tokens consisting of valid non-empty URLs
URLs to ping
User-visible label to be placed within the form control
Encourage the user agent to display video content within the element's playback area
"auto"; "manual"; "hint"; the empty string
Makes the element a popover element
Targets a popover element to toggle, show, or hide
Indicates whether a targeted popover element is to be toggled, shown, or hidden
Poster frame to show prior to video playback
"none"; "metadata"; "auto"; the empty string
Hints how much buffering the media resource will likely need
Whether to allow the value to be edited by the user
Affects willValidate, plus any behavior added by the custom element author
Referrer policy for fetches initiated by the element
Relationship between the location in the document containing the hyperlink and the destination resource
Relationship between the document containing the hyperlink and the destination resource
Whether the control is required for form submission
Number the list backwards
Number of lines to show
Number of rows that the cell is to span
Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of "allow-downloads""allow-forms""allow-modals""allow-orientation-lock""allow-pointer-lock""allow-popups""allow-popups-to-escape-sandbox""allow-presentation""allow-same-origin""allow-scripts""allow-top-navigation""allow-top-navigation-by-user-activation""allow-top-navigation-to-custom-protocols"
Security rules for nested content
Specifies which cells the header cell applies to
Whether the option is selected by default
Sets clonable on a declarative shadow root
Enables declarative shadow roots to indicate they will use a custom element registry
Sets delegates focus on a declarative shadow root
Enables streaming declarative shadow roots
Sets serializable on a declarative shadow root
Sets slot assignment on a declarative shadow root
The kind of shape to be created in an image map
Size of the control
Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of sizes*
Sizes of the icons (for rel="icon")
Image sizes for different page layouts
The element's desired slot
Number of columns spanned by the element
Whether the element is to have its spelling and grammar checked
The source of an iframe srcdoc document*
A document to render in the iframe
Language of the text track
Images to use in different situations, e.g., high-resolution displays, small monitors, etc.
Starting value of the list
Valid floating-point number greater than zero, or "any"
Granularity to be matched by the form control's value
Presentational and formatting instructions
Whether the element is focusable and sequentially focusable, and the relative order of the element for the purposes of sequential focus navigation
Navigable for hyperlink navigation
Default navigable for hyperlink navigation and form submission
Advisory information for the element
Full term or expansion of abbreviation
Description of pattern (when used with pattern attribute)
Title of the link
CSS style sheet set name
Whether the element is to be translated when the page is localized
Hint for the type of the referenced resource
Type of button
Type of embedded resource
Type of form control
Kind of list marker
"module"; "importmap"; "speculationrules"; a valid MIME type string that is not a JavaScript MIME type essence match
Type of script
Name of image map to use
Value to be used for form submission
Value of the form control
Ordinal value of the list item
Current value of the element
Horizontal dimension
How the value of the form control is to be wrapped for form submission
Whether the element can offer writing suggestions or not.
area (if it is a descendant of a map element)
audio (if the controls attribute is present)
if the element's children include at least one name-value group
dl (if the element's children include at least one name-value group)
if the usemap or controls attribute is present
img (if the usemap or controls attribute is present)
if the type attribute is not in the Hidden state
input (if the type attribute is not in the Hidden state)
if it is a hierarchically correct main element
main (if it is a hierarchically correct main element)
if the element's children include at least one li element
menu (if the element's children include at least one li element)
meta (if the itemprop attribute is present)
ol (if the element's children include at least one li element)
ul (if the element's children include at least one li element)
video (if the controls attribute is present)
Text that is not inter-element whitespace