Web/HTML/Link types

From Get docs


In HTML, link types indicate the relationship between two documents, in which one links to the other using an <a>, <area>, <form>, or <link> element.

List of the defined link types and their significance in HTML
Link Type Description Allowed in these elements Not allowed in these elements
alternate
  • If the element is <link> and the rel attribute also contains the stylesheet type, the link defines an alternative style sheet; in that case the title attribute must be present and not be the empty string.
  • If the type is set to application/rss+xml or application/atom+xml, the link defines a syndication feed. The first one defined on the page is the default.
  • Otherwise, the link defines an alternative page, of one of these types:
    • for another medium, like a handheld device (if the media attribute is set)
    • in another language (if the hreflang attribute is set),
    • in another format, such as a PDF (if the type attribute is set)
    • a combination of these
<a>, <area>, <link> <form>
archives ' Defines a hyperlink to a document that contains an archive link to this one. For example, a blog entry could link to a monthly index page this way.

Note: Although recognized, the singular archive is incorrect and must be avoided.

<a>, <area>, <link> <form>
author Defines a hyperlink to a page describing the author or providing a way to contact the author.

Note: This may be a mailto: hyperlink, but this is not recommended on public pages as robot harvesters will quickly lead to a lot of spam sent to the address. In that case, it is better to lead to a page containing a contact form. Although recognized, the rev attribute on <a>, <area> or<link> elements with a link type of made is incorrect and should be replaced by the rel attribute with this link type.

<a>, <area>, <link> <form>
bookmark Indicates that the hyperlink is a permalink for the nearest ancestor <article> element. If none, it is a permalink for the section that the element is most closely associated to.

This allows for bookmarking a single article in a page containing multiple articles, such as on a monthly summary blog page, or a blog aggregator.

<a>, <area> <link>, <form>
canonical From Wikipedia, the free encyclopedia: Canonical_link_element

A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical" or "preferred" version of a web page as part of search engine optimization.

<link> <a>, <area>, <form>
dns-prefetch ' Hints to the browser that a resource is needed, allowing the browser to do a DNS lookup and protocol handshaking before a user clicks the link. <link> <a>, <area>, <form>
external Indicates that the hyperlink leads to a resource outside the site of the current page; that is, following the link will make the user leave the site. <a>, <area>, <form> <link>
first ' Indicates that the hyperlink leads to the first resource of the sequence the current page is in.

Note: Other link types related to linking resources in the same sequence are last, prev, next. Although recognized, the synonyms begin and start are incorrect and must be avoided.

<a>, <area>, <link> <form>
help
  • If the element is <a> or <area>, it indicates that the hyperlink leads to a resource giving further help about the parent of the element, and its descendants.
  • If the element is <link> it indicates that the hyperlink leads to a resource giving further help about the page as a whole.
<a>, <area>, <form>, <link> None.
icon Defines a resource for representing the page in the user interface, usually an icon (auditory or visual). In the browser, it is usually referred to as the favicon.

If there are multiple <link rel="icon">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: 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. 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> <a>, <area>, <form>
import ' HTML Imports <link> <a>, <area>, <form>
index Obsolete since HTML5 Indicates that the page is part of a hierarchical structure and that the hyperlink leads to the top level resource of that structure.

If one or several up link types are also present, the number of these up indicates the depth of the current page in the hierarchy.

<a>, <area>, <link> <form>
last ' Indicates that the hyperlink leads to the last resource of the sequence the current page is in.

Note: Other link types related to linking resources in the same sequence are first, prev, next. Although recognized, the synonym end is incorrect and must be avoided.

<a>, <area>, <link> <form>
license Indicates that the hyperlink leads to a document describing the licensing information. If not inside the <head> element, the standard doesn't distinguish between a hyperlink applying to a specific part of the document or to the document as a whole. Only the data on the page can indicate this.

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

<a>, <area>, <form>, <link> None.
manifest Indicates that the linked file is a Web App Manifest. <link> <a>, <area>, <form>
modulepreload Initiates early (and high-priority) loading of module scripts. <link> <a>, <area>, <form>
next Indicates that the hyperlink leads to the next resource of the sequence the current page is in.

Note: Other link types related to linking resources in the same sequence are first, prev, last.

<a>, <area>, <form>, <link> None.
nofollow Indicates that the linked document is not endorsed by the author of this one, for example if it has no control over it, if it is a bad example or if there is commercial relationship between the two (sold link). This link type may be used by some search engines that use popularity ranking techniques. <a>, <area>, <form> <link>
noopener

Instructs the browser to open the link without granting the new browsing context access to the document that opened it — by not setting the Window.opener property on the opened window (it returns null). This is especially useful when opening untrusted links, in order to ensure they cannot tamper with the originating document via the Window.opener property (see About rel=noopener for more details), while still providing the Referer HTTP header (unless noreferrer is used as well).

Note that when noopener is used, nonempty target names other than _top, _self, and _parent are all treated like _blank in terms of deciding whether to open a new window/tab.

<a>, <area>, <form> <link>
noreferrer Prevents the browser, when navigating to another page, to send this page address, or any other value, as referrer via the Referer: HTTP header.

(In Firefox, before Firefox 37, this worked only in links found in pages. Links clicked in the UI, like "Open in a new tab" via the contextual menu, ignored this).

<a>, <area>, <form> <link>
opener ' Reverts implicit rel="noopener" addition on links with target="_blank" (See related HTML spec discussion, WebKit change, and Firefox bug discussion). <a>, <area>, <form> <link>
pingback Defines an external resource URI to call if one wishes to make a comment or a citation about the webpage. The protocol used to make such a call is defined in the Pingback 1.0 specification.

Note: if the X-Pingback: HTTP header is also present, it supersedes the <link> element with this link type.

<link> <a>, <area>, <form>
preconnect ' Provides a hint to the browser suggesting that it open a connection to the linked web site 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. <link> <a>, <area>, <form>
prefetch Suggests that the browser fetch the linked resource in advance, as it is likely to be requested by the user. Starting with Firefox 44, the value of the crossorigin attribute is taken into consideration, making it possible to make anonymous prefetches.

Note: The Link Prefetch FAQ has details on which links can be prefetched and on alternative methods.

<link> <a>, <area>, <form>
preload Tells the browser to download a resource because this resource will be needed later during the current navigation. See Preloading content with rel="preload" for more details. <link> <a>, <area>, <form>
prerender ' Suggests that the browser fetch the linked resource in advance, and that it also render the prefetched content offscreen so it can be quickly presented to the user once needed. <link> <a>, <area>, <form>
prev Indicates that the hyperlink leads to the preceding resource of the sequence the current page is in.

Note: You can also use the next keyword to specify a link to the next page in the sequence. Although recognized, the synonym previous is incorrect and must be avoided.

<a>, <area>, <link>, <form> None.
search Indicates that the hyperlink references a document whose interface is specially designed for searching in this document, or site, and its resources.

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 some browsers like Firefox or Internet Explorer.

<a>, <area>, <link>, <form> None.
shortlink shortlink Specification

From Wikipedia, the free encyclopedia: URL shortening Some websites create short links to make sharing links via instant messaging easier.

<link> ???
sidebar ' Obsolete since Gecko 63 Indicates that the hyperlink leads to a resource that would be better suited for a secondary browsing context, like a sidebar. Browsers, that don't have such a context will ignore this keyword.

While once part of the HTML specification, this has been removed from the spec and is only implemented by versions of Firefox prior to Firefox 63.

<a>, <area>, <link> <form>
stylesheet Defines an external resource to be used as a stylesheet. If the type is not set, the browser should assume it is a text/css stylesheet until further inspection.

If used in combination with the alternate keyword, it defines an alternative style sheet; in that case the title attribute must be present and not be the empty string.

<link> <a>, <area>, <form>
tag Indicates that the hyperlink refers to a document describing a tag that applies to this document.

Note: This link type should not be set on links to a member of a tag cloud as these do not apply to a single document but to a set of pages.

<a>, <area> <link>, <form>
up ' Indicates that the page is part of a hierarchical structure and that the hyperlink leads to the higher level resource of that structure.

The number of up link types indicates the depth difference between the current page and the linked resource.

<a>, <area>, <link> <form>

Specifications

Specification Status Comment
PreloadThe definition of 'preload' in that specification. Candidate Recommendation Added preload.
Resource HintsThe definition of 'preconnect' in that specification. Working Draft Added dns-prefetch, preconnect, and prerender values.
HTML Living StandardThe definition of 'link types' in that specification. Living Standard Added opener and made noopener the default behavior for target="_blank" links.
HTML5The definition of 'link types' in that specification. Recommendation Added tag, search, prefetch, noreferrer, nofollow, icon, and author.

Renamed copyright to license. Removed start, chapter, section, subsection, and appendix

HTML 4.01 SpecificationThe definition of 'link types' in that specification. Recommendation Added alternate, stylesheet, start, chapter, section, subsection, appendix, and bookmark.

Renamed previous to prev. Removed top, and search.

UnknownThe definition of '<link>' in that specification. Obsolete Added top, contents, index, glossary, copyright, next, previous, help, and search.
RFC 1866: HTML 2.0 Obsolete Initial definition.

Browser compatibility

Update compatibility data on GitHub

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
rel Chrome

Full support 1

Edge

Full support 12

Firefox

Full support 1

IE

Full support Yes

Opera

Full support Yes

Safari

Full support Yes

WebView Android

Full support Yes

Chrome Android

Full support Yes

Firefox Android

Full support 4

Opera Android

Full support Yes

Safari iOS

Full support Yes

Samsung Internet Android

Full support Yes

Alternative stylesheets. Chrome

No support 1 — 48

Edge

?

Firefox

Full support 3

IE

Full support 8

Opera

Full support Yes

Safari

?

WebView Android

?

Chrome Android

?

Firefox Android

Full support 4

Opera Android

?

Safari iOS

?

Samsung Internet Android

?

dns-prefetch

Experimental'

Chrome

Full support 46

Edge

Full support ≤79

Firefox

Full support 3

IE

?

Opera

Full support 33

Safari

?

WebView Android

Full support 46

Chrome Android

Full support Yes

Firefox Android

Full support 4

Opera Android

?

Safari iOS

?

Samsung Internet Android

Full support Yes

icon

Chrome Full support 4

Notes'

Full support 4

Notes'

Notes' If both ICO and PNG are available, will use ICO over PNG if ICO has better matching sizes set. (Per caniuse.com.)

Edge Full support 12

Notes'

Full support 12

Notes'

Notes' In version 79 and later (Blink-based Edge), if both ICO and PNG are available, will use ICO over PNG if ICO has better matching sizes set. (Per caniuse.com.)

Firefox

Full support 2

IE

Full support 11

Opera Full support 9

Notes'

Full support 9

Notes'

Notes' In version 15 and later (Blink-based Opera), if both ICO and PNG are available, will use ICO over PNG if ICO has better matching sizes set. (Per caniuse.com.)

Safari Full support 3.1

Notes'

Full support 3.1

Notes'

Notes' If both ICO and PNG are available, will ALWAYS use ICO file, regardless of sizes set. (Per caniuse.com.)

WebView Android

Full support 38

Chrome Android

Full support 18

Firefox Android

Full support 4

Opera Android

No support No

Safari iOS No support No

Notes'

No support No

Notes'

Notes' Does not use favicons at all (but may have alternative for bookmarks, etc.). (Per caniuse.com.)

Samsung Internet Android

Full support 4.0

manifest

Experimental'Non-standard'

Chrome

No support No

Edge

No support No

Firefox

?

IE

?

Opera

No support No

Safari

?

WebView Android

Full support 39

Chrome Android

Full support 39

Firefox Android

?

Opera Android

?

Safari iOS

?

Samsung Internet Android

Full support 4.0

modulepreload

Experimental'

Chrome

Full support 66

Edge

Full support ≤79

Firefox

?

IE

?

Opera

Full support 53

Safari

?

WebView Android

Full support 66

Chrome Android

Full support 66

Firefox Android

?

Opera Android

Full support 47

Safari iOS

?

Samsung Internet Android

Full support 9.0

preconnect

Experimental'

Chrome

Full support 46

Edge

Full support 79

Firefox Full support 39

Notes'

Full support 39

Notes'

Notes' Before Firefox 41, it doesn't obey the crossorigin attribute.

IE

No support No

Opera

Full support 33

Safari

Full support 11.1

WebView Android

Full support 46

Chrome Android

Full support 46

Firefox Android Full support 39

Notes'

Full support 39

Notes'

Notes' Before Firefox 41, it doesn't obey the crossorigin attribute.

Opera Android

Full support 33

Safari iOS

Full support 11.3

Samsung Internet Android

Full support 4.0

prefetch

Experimental'

Chrome

Full support 8

Edge

Full support 12

Firefox

Full support 2

IE

Full support 11

Opera

Full support 15

Safari

No support No

WebView Android

Full support 4.4

Chrome Android

Full support 18

Firefox Android

Full support 4

Opera Android

Full support 14

Safari iOS

No support No

Samsung Internet Android

Full support 1.5

preload

Experimental'

Chrome

Full support 50

Edge

Full support ≤79

Firefox No support 56 — 57

Notes'

No support 56 — 57

Notes'

Notes' Disabled due to various web compatibility issues (e.g. bug 1405761).

IE

?

Opera

Full support 37

Safari

?

WebView Android

Full support 50

Chrome Android

Full support 50

Firefox Android No support 56 — 57

Notes'

No support 56 — 57

Notes'

Notes' Disabled due to various web compatibility issues (e.g. bug 1405761).

Opera Android

?

Safari iOS

?

Samsung Internet Android

Full support 5.0

prerender

Experimental'

Chrome

Full support 13

Edge

Full support 79

Firefox

No support No

IE

Full support 11

Opera

Full support 15

Safari

No support No

WebView Android

Full support 4.4

Chrome Android

Full support 18

Firefox Android

No support No

Opera Android

Full support 14

Safari iOS

No support No

Samsung Internet Android

Full support 1.5

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.'
Experimental. Expect behavior to change in the future.
Non-standard. Expect poor cross-browser support.'
Non-standard. Expect poor cross-browser support.
See implementation notes.'
See implementation notes.