What is rel attribute in html

HTML attribute: rel

The rel attribute defines the relationship between a linked resource and the current document. Valid on , , , and , the supported values depend on the element on which the attribute is found.

The type of relationships is given by the value of the rel attribute, which, if present, must have a value that is an unordered set of unique space-separated keywords. Differently from a class name, which does not express semantics, the rel attribute must express tokens that are semantically valid for both machines and humans. The current registries for the possible values of the rel attribute are the IANA link relation registry, the HTML Living Standard, and the freely-editable existing-rel-values page in the microformats wiki, as suggested by the Living Standard. If a rel attribute not present in one of the three sources above is used some HTML validators (such as the W3C Markup Validation Service) will generate a warning.

The following table lists some of the most important existing keywords. Every keyword within a space-separated value should be unique within that value.

rel value Description and
alternate Alternate representations of the current document. Link Link Not allowed
author Author of the current document or article. Link Link Not allowed
bookmark Permalink for the nearest ancestor section. Not allowed Link Not allowed
canonical Preferred URL for the current document. Link Not allowed Not allowed
dns-prefetch Tells the browser to preemptively perform DNS resolution for the target resource’s origin. External Resource Not allowed Not allowed
external The referenced document is not part of the same site as the current document. Not allowed Annotation Annotation
help Link to context-sensitive help. Link Link Link
icon An icon representing the current document. External Resource Not allowed Not allowed
license Indicates that the main content of the current document is covered by the copyright license. described by the referenced document. Link Link Link
manifest Web app manifest. Link Not allowed Not allowed
me Indicates that the current document represents the person who owns the linked content. Link Link Not allowed
modulepreload Tells to browser to preemptively fetch the script and store it in the document’s module map for later evaluation. Optionally, the module’s dependencies can be fetched as well. External Resource Not allowed Not allowed
next Indicates that the current document is a part of a series and that the next document in the series is the referenced document. Link Link Link
nofollow Indicates that the current document’s original author or publisher does not endorse the referenced document. Not allowed Annotation Annotation
noopener Creates a top-level browsing context that is not an auxiliary browsing context if the hyperlink would create either of those, to begin with (i.e., has an appropriate target attribute value). Not allowed Annotation Annotation
noreferrer No Referer header will be included. Additionally, has the same effect as noopener . Not allowed Annotation Annotation
opener Creates an auxiliary browsing context if the hyperlink would otherwise create a top-level browsing context that is not an auxiliary browsing context (i.e., has » _blank » as target attribute value). Not allowed Annotation Annotation
pingback Gives the address of the pingback server that handles pingbacks to the current document. External Resource Not allowed Not allowed
preconnect Specifies that the user agent should preemptively connect to the target resource’s origin. External Resource Not allowed Not allowed
prefetch Specifies that the user agent should preemptively fetch and cache the target resource as it is likely to be required for a followup navigation. External Resource Not allowed Not allowed
preload Specifies that the user agent must preemptively fetch and cache the target resource for current navigation according to the potential destination given by the as attribute (and the priority associated with the corresponding destination). External Resource Not allowed Not allowed
prerender Specifies that the user agent should preemptively fetch the target resource and process it in a way that helps deliver a faster response in the future. External Resource Not allowed Not allowed
prev Indicates that the current document is a part of a series and that the previous document in the series is the referenced document. Link Link Link
search Gives a link to a resource that can be used to search through the current document and its related pages. Link Link Link
stylesheet Imports a style sheet. External Resource Not allowed Not allowed
tag Gives a tag (identified by the given address) that applies to the current document. Not allowed Link Not allowed

The rel attribute has no default value. If the attribute is omitted or if none of the values in the attribute are supported, then the document has no particular relationship with the destination resource other than there being a hyperlink between the two. In this case, on and , if the rel attribute is absent, has no keywords, or if not one or more of the space-separated keywords above, then the element does not create any links. and will still created links, but without a defined relationship.

Values

Indicates an alternate representation of the current document. Valid for , , and , the meaning depends on the values of the other attributes.

link rel="stylesheet" href="default.css" /> link rel="alternate stylesheet" href="highcontrast.css" title="High contrast" /> 
link rel="alternate" type="application/atom+xml" href="posts.xml" title="Blog" /> 
  • If hreflang is given alongside alternate , and the value of hreflang is different from the current document’s language, it indicates that the referenced document is a translation.
  • If type is given alongside alternate , it indicates that the referenced document is an alternative format (such as a PDF).
  • The hreflang and type attributes may both be given alongside alternate .
link rel="alternate" href="/fr/html/print" hreflang="fr" type="text/html" media="print" title="French HTML (for printing)" /> link rel="alternate" href="/fr/pdf" hreflang="fr" type="application/pdf" title="French PDF" /> 

Indicates the referenced document provides further information about the author of the current document or article. Relevant for , , and elements.

Note: For historical reasons, the obsolete attribute value rev=»made» is treated as rel=»author» .

The most common use for the icon value is the favicon:

link rel="icon" href="favicon.ico" /> 

If there are multiple s, the browser uses their media , type , and sizes attributes to select the most appropriate icon. If several icons are equally appropriate, the last one is used. If the most appropriate icon is later found to be inappropriate, for example because it uses an unsupported format, the browser proceeds to the next-most appropriate, and so on.

Note: The crossorigin attribute is not supported for rel=»icon» in Chromium-based browsers. See the open Chromium issue.

Note: Apple’s iOS does not use this link type, nor the sizes attribute, like others mobile browsers do, to select a webpage icon for Web Clip or a start-up placeholder. Instead it uses the non-standard apple-touch-icon and apple-touch-startup-image respectively.

Note: The shortcut link type is often seen before icon , but this link type is non-conforming, ignored and web authors must not use it anymore.

link rel="license" href="#license" /> 

Note: Although recognized, the synonym copyright is incorrect and must be avoided.

Web app manifest. Requires the use of the CORS protocol for cross-origin fetching.

Creates an auxiliary browsing context if the hyperlink would otherwise create a top-level browsing context that is not an auxiliary browsing context (i.e., has » _blank » as target attribute value). Effectively, the opposite of noopener.

Gives the address of the pingback server that handles pingbacks to the current document. See the Pingback specification.

Provides a hint to the browser suggesting that it open a connection to the linked website in advance, without disclosing any private information or downloading any content, so that when the link is followed the linked content can be fetched more quickly.

Specifies that the user agent should preemptively fetch and cache the target resource as it is likely to be required for a followup navigation. See prefetch for more information.

Specifies that the user agent must preemptively fetch and cache the target resource for current navigation according to the potential destination given by the as attribute (and the priority associated with the corresponding destination). See the page for the preload value.

prerender Deprecated Non-standard

Specifies that the user agent should preemptively fetch the target resource and process it in a way that helps deliver a faster response in the future, for example by fetching its subresources or performing some rendering.

Note: The synonym previous is incorrect and should not be used.

If the type attribute is set to application/opensearchdescription+xml the resource is an OpenSearch plugin that can be easily added to the interface of Firefox.

Valid for the element, it imports an external resource to be used as a stylesheet. The type attribute is not needed as it’s a text/css stylesheet, as that is the default value. If it’s not a stylesheet of type text/css it is best to declare the type.

While this attribute defines the link as being a stylesheet, the interaction with other attributes and other key terms within the rel value impact whether the stylesheet is downloaded and/or used.

When used with the alternate keyword, it defines an alternative style sheet. In this case, include a non-empty title .

The external stylesheet will not be used or even downloaded if the media does not match the value of the media attribute.

Requires the use of the CORS protocol for cross-origin fetching.

Non-standard values

Specifies the icon for a web application on an iOS device.

Specifications

Browser compatibility

BCD tables only load in the browser

html.elements.a.rel

BCD tables only load in the browser

html.elements.area.rel

BCD tables only load in the browser

See also

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This page was last modified on Jun 30, 2023 by MDN contributors.

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HTML rel Attribute

The rel attribute specifies the relationship between the current document and the linked document.

Only used if the href attribute is present.

Tip: Search engines can use this attribute to get more information about a link!

Browser Support

Syntax

Attribute Values

Value Description
alternate Provides a link to an alternate representation of the document (i.e. print page, translated or mirror)
author Provides a link to the author of the document
bookmark Permanent URL used for bookmarking
external Indicates that the referenced document is not part of the same site as the current document
help Provides a link to a help document
license Provides a link to licensing information for the document
next Provides a link to the next document in the series
nofollow Links to an unendorsed document, like a paid link.
(«nofollow» is used by Google, to specify that the Google search spider should not follow that link)
noopener Requires that any browsing context created by following the hyperlink must not have an opener browsing context
noreferrer Makes the referrer unknown. No referer header will be included when the user clicks the hyperlink
prev The previous document in a selection
search Links to a search tool for the document
tag A tag (keyword) for the current document

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