The HTML specification defines the following set of standard metadata names:
application-name: the name of the application running in the web page.
<title>element, which usually contain the application name, but may also contain information like the document name or a status.
author: the name of the document's author.
description: a short and accurate summary of the content of the page. Several browsers, like Firefox and Opera, use this as the default description of bookmarked pages.
generator: the identifier of the software that generated the page.
keywords: words relevant to the page's content separated by commas.
referrer: controls the HTTP
Refererheader for to requests sent from the document:
| ||Do not send a HTTP |
| ||Send the origin of the document.|
| ||Send the full URL when the destination is at least as secure as the current page (HTTP(S)→HTTPS), but send no referrer when it's less secure (HTTPS→HTTP). This is the default behaviour.|
| ||Send the full URL (stripped of parameters) for same-origin requests, but only send the origin for other cases.|
| ||Send the full URL (stripped of parameters) for same-origin requests. Cross-origin requests will contain no referrer header.|
| ||Send the origin when the destination is at least as secure as the current page (HTTP(S)→HTTPS), but send no referrer when it's less secure (HTTPS→HTTP).|
| ||Send the full URL (stripped of parameters) for same-origin requests. Send the origin when the destination is at least as secure as the current page (HTTP(S)→HTTPS). Otherwise, send no referrer.|
| ||Send the full URL (stripped of parameters) for same-origin or cross-origin requests.|
theme-color: indicates a suggested color that user agents should use to customize the display of the page or of the surrounding user interface. The
contentattribute contains a valid CSS
color-scheme: specifies one or more color schemes with which the document is compatible.
The browser will use this information in tandem with the user's browser or device settings to determine what colors to use for everything from background and foregrounds to form controls and scrollbars. The primary use for
<meta name="color-scheme"> is to indicate compatibility with—and order of preference for—light and dark color modes.
The value of the
content property for
color-scheme may be one of the following:
only darkis not valid, because forcing a document to render in dark mode when it isn't truly compatible with it can result in unreadable content; all major browsers default to light mode if not otherwise configured.
For example, to indicate that a document prefers dark mode but does render functionally in light mode as well:
<meta name="color-scheme" content="dark light">
This works at the document level in the same way that the CSS
color-scheme property lets individual elements specify their preferred and accepted color schemes. Your styles can adapt to the current color scheme using the
prefers-color-scheme CSS media feature.
The CSS Device Adaptation specification defines the following metadata name:
viewport: gives hints about the size of the initial size of the viewport. Used by mobile devices only.
| ||A positive integer number, or the text ||Defines the pixel width of the viewport that you want the web site to be rendered at.|
| ||A positive integer, or the text ||Defines the height of the viewport. Not used by any browser.|
| ||A positive number between ||Defines the ratio between the device width ( |
| ||A positive number between ||Defines the maximum amount to zoom in. It must be greater or equal to the |
| ||A positive number between ||Defines the minimum zoom level. It must be smaller or equal to the |
||If set to |
user-scalableto a value of
noprevents people experiencing low vision conditions from being able to read and understand page content.
@viewport CSS at-rule.
The WHATWG Wiki MetaExtensions page contains a large set of non-standard metadata names that have not been formally accepted yet; however, some of the names included there are already used quite commonly in practice — including the following:
creator: the name of the creator of the document, such as an organization or institution. If there are more than one, several
<meta>elements should be used.
googlebot, a synonym of
robots, is only followed by Googlebot (the indexing crawler for Google).
publisher: the name of the document's publisher.
robots: the behaviour that cooperative crawlers, or "robots", should use with the page. It is a comma-separated list of the values below:
| ||Allows the robot to index the page (default).||All|
| ||Requests the robot to not index the page.||All|
| ||Allows the robot to follow the links on the page (default).||All|
| ||Requests the robot to not follow the links on the page.||All|
| ||Equivalent to |
| ||Equivalent to |
| ||Requests the search engine not to cache the page content.||Google, Yahoo, Bing|
| ||Prevents displaying any description of the page in search engine results.||Google, Bing|
| ||Requests this page not to appear as the referring page of an indexed image.|
| ||Synonym of ||Bing|
noindexwill work, but only after the robot visits the page again. Ensure that the
robots.txtfile is not preventing revisits.
nofollow. In these cases the robot's behaviour is undefined and may vary between them.
X-Robots-Tag; this allows non-HTML documents like images to use these rules.
|HTML Living Standard |
The definition of 'standard metadata names' in that specification.
|CSS Device Adaptation |
The definition of 'the "viewport" metadata name' in that specification.
|Referrer Policy |
The definition of 'the "referrer" metadata name' in that specification.
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