| Attribute | Element(s) | Description | Value |
|---|---|---|---|
| <{abbr}> | <{th}> | Alternative label to use for the header cell when referencing the cell in other contexts | Text* |
| <{input/accept}> | <{input}> | Hint for expected file type in <{input/File|File Upload}> controls | Set of comma-separated tokens* consisting of valid MIME types with no parameters or audio/*, video/*, or image/* |
| <{form/accept-charset}> | <{form}> | Character encodings to use for form submission | Ordered set of unique space-separated tokens, ASCII case-insensitive, consisting of labels of ASCII-compatible encodings* |
| <{global/accesskey}> | HTML elements | Keyboard shortcut to activate or focus element | Ordered set of unique space-separated tokens, case-sensitive, consisting of one Unicode code point in length |
| <{form/action}> | <{form}> | [=url/URL=] to use for form submission | Valid non-empty URL potentially surrounded by spaces |
| <{iframe/allowfullscreen}> | <{iframe}> | Whether to allow the <{iframe}>'s contents to use {{Element/requestFullscreen()}} | Boolean attribute |
| <{iframe/allowpaymentrequest}> | <{iframe}> | Whether to allow the <{iframe}>'s browsing context to use the PaymentRequest interface to make payment requests. |
Boolean attribute |
| <{iframe/allowusermedia}> | <{iframe}> | Whether to allow the <{iframe}>'s browsing context to use {{Element/getUserMedia()}}. | Boolean attribute |
alt |
<{area}>; <{img}>; <{input}> | Replacement text for use when images are not available | Text* |
| <{script/async}> | <{script}> | Execute script asynchronously | Boolean attribute |
| <{input/autocapitalize}> | <{input}>; <{textarea}> | Hint for the capitalization of the inputted text | "sentences";
"words";
"characters" |
| <{form/autocomplete}> | <{form}> | Default setting for autofill feature for controls in the form | "on"; "off" |
| <{input/autocomplete}> | <{input}>; <{select}>; <{textarea}> | Hint for form autofill feature | Autofill field name and related tokens* |
| <{formelements/autofocus}> | <{button}>; <{input}>; <{select}>; <{textarea}> | Automatically focus the form control when the page is loaded | Boolean attribute |
autoplay |
<{audio}>; <{video}> | Hint that the media resource can be started automatically when the page is loaded | Boolean attribute |
border |
<{table}> | Explicit indication that the <{table}> element is not being used for layout purposes | The empty string, or "1" |
charset |
<{meta}> | Character encoding declaration | utf-8 |
charset |
<{script}> | Character encoding of the external script resource | utf-8 |
checked |
<{input}> | Whether the command or control is checked | Boolean attribute |
cite |
<{blockquote}>; <{del}>; <{ins}>; <{q}> | Link to the source of the quotation or more information about the edit | Valid URL potentially surrounded by spaces |
class |
HTML elements | Classes to which the element belongs | Set of space-separated tokens |
cols |
<{textarea}> | Maximum number of characters per line | Valid non-negative integer greater than zero |
colspan |
<{td}>; <{th}> | Number of columns that the cell is to span | Valid non-negative integer greater than zero |
content |
<{meta}> | Value of the element | Text* |
contenteditable |
HTML elements | Whether the element is editable | "true"; "false" |
controls |
<{audio}>; <{video}> | Show user agent controls | Boolean attribute |
coords |
<{area}> | Coordinates for the shape to be created in an image map | Valid list of floating-point numbers* |
crossorigin |
<{audio}>; <{img}>; <{link}>; <{script}>; <{video}> | How the element handles crossorigin requests | "anonymous"; "use-credentials" |
data |
<{object}> | Address of the resource | Valid non-empty URL potentially surrounded by spaces |
datetime |
<{del}>; <{ins}> | Date and (optionally) time of the change | Valid date string with optional time |
datetime |
<{time}> | Machine-readable value | Valid month string, valid date string, valid yearless date string, valid time string, valid floating 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 |
| <{img/decoding}> | <{img}> | A hint to request a/synchronous loading of images | "sync", "async", "auto" |
default |
<{track}> | Enable the track if no other text track is more suitable | Boolean attribute |
defer |
<{script}> | Defer script execution | Boolean attribute |
dir |
HTML elements | The text directionality of the element | "ltr"; "rtl"; "auto" |
dir |
<{bdo}> | The text directionality of the element | "ltr"; "rtl" |
dirname |
<{input}>; <{textarea}> | Name of form field to use for sending the element's directionality in form submission | Text* |
disabled |
<{button}>; <{fieldset}>; <{input}>; <{optgroup}>; <{option}>; <{select}>; <{textarea}> | Whether the form control is disabled | Boolean attribute |
| <{media/disableRemotePlayback}> | <{audio}>; <{video}> | Whether the remote playback of a media element is disabled | Boolean attribute |
download |
<{a}>; <{area}> | Whether to download the resource instead of navigating to it, and its file name if so | Text |
| <{global/draggable}> | HTML elements | Whether the element is draggable | "true"; "false" |
| <{form/enctype}> | <{form}> | Form data set encoding type to use for form submission | "application/x-www-form-urlencoded"; "multipart/form-data"; "text/plain" |
for |
<{label}> | Associate the label with form control | ID* |
for |
<{output}> | Specifies controls from which the output was calculated | Unordered set of unique space-separated tokens, case-sensitive, consisting of IDs* |
form |
<{button}>; <{fieldset}>; <{input}>; <{label}>; <{object}>; <{output}>; <{select}>; <{textarea}> | Associates the control with a <{form}> element | ID* |
formaction |
<{button}>; <{input}> | [=url/URL=] to use for form submission | Valid non-empty URL potentially surrounded by spaces |
formenctype |
<{button}>; <{input}> | Form data set encoding type to use for form submission | "application/x-www-form-urlencoded"; "multipart/form-data"; "text/plain" |
formmethod |
<{button}>; <{input}> | HTTP method to use for form submission | "GET"; "POST" |
formnovalidate |
<{button}>; <{input}> | Bypass form control validation for form submission | Boolean attribute |
formtarget |
<{button}>; <{input}> | Browsing context for form submission | Valid browsing context name or keyword |
headers |
<{td}>; <{th}> | The header cells for this cell | Unordered set of unique space-separated tokens, case-sensitive, consisting of IDs* |
height |
<{canvas}>; <{embed}>; <{iframe}>; <{img}>; <{input}>; <{object}>; <{video}> | Vertical dimension | Valid non-negative integer |
| <{global/hidden}> | HTML elements | Whether the element is relevant | Boolean attribute |
high |
<{meter}> | Low limit of high range | Valid floating-point number* |
href |
<{a}>; <{area}> | Address of the hyperlink | Valid URL potentially surrounded by spaces |
href |
<{link}> | Address of the hyperlink | Valid non-empty URL potentially surrounded by spaces |
href |
<{base}> | Document base URL | Valid URL potentially surrounded by spaces |
hreflang |
<{a}>; <{area}>; <{link}> | Language of the linked resource | Valid BCP 47 language tag |
http-equiv |
<{meta}> | Pragma directive | Text* |
id |
HTML elements | The element's ID | Text* |
integrity |
<{link}>; <{script}> | Integrity metadata used in Subresource Integrity checks [[!SRI]] | Text |
| <{global/is}> | Customized built-in elements | The local name of the element | A valid custom element name |
ismap |
<{img}> | Whether the image is a server-side image map | Boolean attribute |
kind |
<{track}> | The type of text track | "subtitles"; "captions"; "descriptions"; "chapters"; "metadata" |
label |
<{optgroup}>; <{option}>; <{track}> | User-visible label | Text |
lang |
HTML elements | Language of the element | Valid BCP 47 language tag or the empty string |
| <{input/list}> | <{input}> | List of autocomplete options | ID* |
longdesc |
<{img}> | A link to a fuller description of the image | Valid non-empty URL potentially surrounded by spaces |
loop |
<{audio}>; <{video}> | Whether to loop the media resource | Boolean attribute |
low |
<{meter}> | High limit of low range | Valid floating-point number* |
| <{html/manifest}> | <{html}> | Application cache manifest | a valid non-empty URL potentially surrounded by spaces |
| <{input/max}> | <{input}> | Maximum value | Varies* |
| <{meter/max}> | <{meter}>; <{progress}> | Upper bound of range | Valid floating-point number* |
maxlength |
<{input}>; <{textarea}> | Maximum length of value | Valid non-negative integer |
media |
<{link}>; <{style}> | Applicable media | Valid media query list |
| <{form/method}> | <{form}> | HTTP method to use for form submission | "get"; "post"; "dialog" |
min |
<{input}> | Minimum value | Varies* |
min |
<{meter}> | Lower bound of range | Valid floating-point number* |
minlength |
<{input}>; <{textarea}> | Minimum length of value | Valid non-negative integer |
multiple |
<{input}>; <{select}> | Whether to allow multiple values | Boolean attribute |
muted |
<{audio}>; <{video}> | Whether to mute the media resource by default | Boolean attribute |
name |
<{button}>; <{fieldset}>; <{input}>; <{output}>; <{select}>; <{textarea}> | Name of form control to use for form submission and in the {{HTMLFormElement/elements|form.elements}} API | Text* |
name |
form |
Name of form to use in the document.forms API |
Text* |
name |
<{iframe}>; <{object}> | Name of nested browsing context | Valid browsing context name or keyword |
name |
<{map}> | Name of image map to reference from the usemap attribute |
Text* |
name |
<{meta}> | Metadata name | Text* |
name |
<{param}> | Name of parameter | Text |
nonce |
HTML elements | Cryptographic nonce used in Content Security Policy checks [[CSP3]] | Text |
| <{form/novalidate}> | <{form}> | Bypass form control validation for form submission | Boolean attribute |
open |
<{details}> | Whether the details are visible | Boolean attribute |
open |
<{dialog}> | Whether the dialog box is showing | Boolean attribute |
optimum |
<{meter}> | Optimum value in gauge | Valid floating-point number* |
pattern |
<{input}> | Pattern to be matched by the form control's value | Regular expression matching the JavaScript Pattern production |
ping |
<{a}>, <{area}> | URLs to ping | Set of comma-separated tokens consisting of valid non-empty URLs |
placeholder |
<{input}>; <{textarea}> | User-visible label to be placed within the form control | Text* |
poster |
<{video}> | Poster frame to show prior to video playback | Valid non-empty URL potentially surrounded by spaces |
preload |
<{audio}>; <{video}> | Hints how much buffering the media resource will likely need | "none"; "metadata"; "auto" |
readonly |
<{input}>; <{textarea}> | Whether to allow the value to be edited by the user | Boolean attribute |
referrerpolicy |
<{a}>; <{area}>; <{iframe}>; <{img}>; <{link}> | Referrer policy for fetches initiated by the element | Referrer policy |
| <{links/rel}> | <{a}>; <{area}>; <{link}> | Relationship of this document (or subsection/topic) to the destination resource | Set of space-separated tokens* |
required |
<{input}>; <{select}>; <{textarea}> | Whether the control is required for form submission | Boolean attribute |
| <{links/rev}> | <{a}>; <{link}> | Reverse link relationship of the destination resource to this document (or subsection/topic) | Set of space-separated tokens |
reversed |
<{ol}> | Number the list backwards | Boolean attribute |
rows |
<{textarea}> | Number of lines to show | Valid non-negative integer greater than zero |
rowspan |
<{td}>; <{th}> | Number of rows that the cell is to span | Valid non-negative integer |
| <{iframe/sandbox}> | <{iframe}> | Security rules for nested content |
Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of
"allow-forms",
"allow-pointer-lock",
"allow-popups",
"allow-presentation",
"allow-same-origin",
"allow-scripts and
"allow-top-navigation"
|
scope |
<{th}> | Specifies which cells the header cell applies to | "row"; "col"; "rowgroup"; "colgroup" |
selected |
<{option}> | Whether the option is selected by default | Boolean attribute |
shape |
<{area}> | The kind of shape to be created in an image map | "circle"; "default"; "poly"; "rect" |
size |
<{input}>; <{select}> | Size of the control | Valid non-negative integer greater than zero |
sizes |
<{link}> | Sizes of the icons (for <{link/rel}>="icon") |
Unordered set of unique space-separated tokens, ASCII case-insensitive, consisting of sizes* |
sizes |
<{img}>; <{source}> | Image sizes for different page layouts | Valid source size list |
span |
<{col}>; <{colgroup}> | Number of columns spanned by the element | Valid non-negative integer greater than zero |
| <{global/spellcheck}> | HTML elements | Whether the element is to have its spelling and grammar checked | "true"; "false" |
src |
<{audio}>; <{embed}>; <{iframe}>; <{img}>; <{input}>; <{script}>; <{source}>; <{track}>; <{video}> | Address of the resource | Valid non-empty URL potentially surrounded by spaces |
srcdoc |
<{iframe}> | A document to render in the <{iframe}> | The source of an `iframe` `srcdoc` document* |
srclang |
<{track}> | Language of the text track | Valid BCP 47 language tag |
srcset |
<{img}>; <{source}> | Images to use in different situations (e.g., high-resolution displays, small monitors, etc) | Comma-separated list of image candidate strings |
start |
<{ol}> | Ordinal value of the first item | Valid integer |
| <{input/step}> | <{input}> | Granularity to be matched by the form control's value | Valid floating-point number greater than zero, or "any" |
style |
HTML elements | Presentational and formatting instructions | CSS declarations* |
| <{global/tabindex}> | HTML elements | Whether the element is focusable, and the relative order of the element for the purposes of sequential focus navigation | Valid integer |
target |
<{a}>; <{area}> | Browsing context for hyperlink navigation | Valid browsing context name or keyword |
| <{base/target}> | <{base}> | Default browsing context for hyperlink navigation and form submission | Valid browsing context name or keyword |
| <{form/target}> | <{form}> | Browsing context for form submission | Valid browsing context name or keyword |
| <{global/title}> | HTML elements | Advisory information for the element | Text |
| <{abbr/title}> | <{abbr}>; <{dfn}> | Full term or expansion of abbreviation | Text |
| <{input/title}> | <{input}> | Description of pattern (when used with pattern attribute) |
Text |
| <{link/title}> | <{link}> | Title of the link | Text |
title |
<{link/title|link}>; <{style/title|style}> | Alternative style sheet set name | Text |
| <{global/translate}> | HTML elements | Whether the element is to be translated when the page is localized | "yes"; "no" |
type |
<{a}>; <{area}>; <{link}> | Hint for the type of the referenced resource | Valid MIME type |
| <{button/type}> | <{button}> | Type of button | "submit"; "reset"; "button" |
type |
<{embed}>; <{object}>; <{script}>; <{source}>; <{style}> | Type of embedded resource | Valid MIME type |
type |
<{input}> | Type of form control | input type keyword |
type |
<{ol}> | Kind of list marker | "1"; "a"; "A"; "i"; "I" |
typemustmatch |
<{object}> | Whether the <{object/type}> attribute and the Content-Type value need to match for the resource to be used | Boolean attribute |
usemap |
<{img}> | Name of image map to use | Valid hash-name reference* |
value |
<{button}>; <{option}> | Value to be used for form submission | Text |
value |
<{data}> | Machine-readable value | Text* |
value |
<{input}> | Value of the form control | Varies* |
value |
<{li}> | Ordinal value of the list item | Valid integer |
value |
<{meter}>; <{progress}> | Current value of the element | Valid floating-point number |
value |
<{param}> | Value of parameter | Text |
width |
<{canvas}>; <{embed}>; <{iframe}>; <{img}>; <{input}>; <{object}>; <{video}> | Horizontal dimension | Valid non-negative integer |
wrap |
<{textarea}> | How the value of the form control is to be wrapped for form submission | "soft"; "hard" |
An asterisk (*) in a cell indicates that the actual rules are more complicated than indicated in the table above.