HTML 5 <link> Tag

The HTML <link> tag is used for defining a link to an external resource. It is placed in in the <head> section of the HTML document.

The <link> tag is commonly used for linking to an external style sheet. But it can also be used for other purposes such as assisting search engines by providing links to relevant resources, and providing information on the website's navigational structure, etc.

Although the <link> tag creates what is referred to as a "hyperlink", it is not used for creating the "clickable" hyperlink that most web users are familiar with. To create such a link, use the <a> tag.

Example

This example references styles an external style sheet. The external style sheet is linked to the document with the <link> tag.

Attributes

HTML tags can contain one or more attributes. Attributes are added to a tag to provide the browser with more information about how the tag should appear or behave. Attributes consist of a name and a value separated by an equals (=) sign, with the value surrounded by double quotes. Here's an example, style="color:black;".

There are 3 kinds of attributes that you can add to your HTML tags: Element-specific, global, and event handler content attributes.

The attributes that you can add to this tag are listed below.

Element-Specific Attributes

The following table shows the attributes that are specific to this tag/element.

AttributeDescription
hrefSpecifies the URL of the resource document.
crossoriginThis attribute is a CORS settings attribute. CORS stands for Cross-Origin Resource Sharing. The purpose of the crossorigin attribute is to allow you to configure the CORS requests for the element's fetched data. The values for the crossorigin attribute are enumerated.

Possible values:

ValueDescription
anonymousCross-origin CORS requests for the element will not have the credentials flag set. In other words, there will be no exchange of user credentials via cookies, client-side SSL certificates or HTTP authentication.
use-credentialsCross-origin CORS requests for the element will have the credentials flag set.

If this attribute is not specified, CORS is not used at all.

An invalid keyword and an empty string will be handled as the anonymous value.

relDescribes the relationship between the current document and the destination URI. Multiple values can be provided, separated by a space.

Possible values:

ValueDescription
alternateGives alternate representations of the current document. For example, here is sample code (taken from the HTML5 specification) for giving the syndication feed for the current page: <link rel="alternate" type="application/atom+xml" href="data.xml">
canonicalGives the preferred URL for the current document.
authorGives a link to the current document's author.
dns-prefetchSpecifies that the user agent should preemptively perform DNS resolution for the target resource's origin.
helpProvides a link to context-sensitive help.
iconImports an icon to represent the current document.
modulepreloadSpecifies that the user agent must preemptively fetch the module script and store it in the document's module map for later evaluation. Optionally, the module's dependencies can be fetched as well.
licenseIndicates that the main content of the current document is covered by the copyright license described by the referenced document.
nextIndicates that the current document is a part of a series, and that the next document in the series is the referenced document.
pingbackGives the address of the pingback server that handles pingbacks to the current document.
preconnectSpecifies that the user agent should preemptively connect to the target resource's origin.
prefetchSpecifies that the user agent should preemptively fetch and cache the target resource as it is likely to be required for a followup navigation.
preloadSpecifies 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).
prerenderSpecifies 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.
prevIndicates that the current document is a part of a series, and that the previous document in the series is the referenced document.
searchGives a link to a resource that can be used to search through the current document and its related pages.
stylesheetImports an external stylesheet.
revReverse link relationship of the destination resource to this document (or subsection/topic).
mediaSpecifies which media the target URL uses. Only to be used when the href attribute is present.

Value:

[The value must be a valid media query. The default value is all].

nonceRepresents a cryptographic nonce ("number used once") which can be used by Content Security Policy to determine whether or not an external resource specified by the link will be loaded and applied to the document. The value is text.
hreflangLanguage code of the destination URL. Purely advisory. The value must be a valid RFC 3066 language code.
typeThe MIME type of content at the link destination. Purely advisory.
referrerpolicyReferrer policy for fetches initiated by the element.
sizesSpecifies the sizes of icons for visual media. Can be used for favicons. Multiple values can be provided, as long as they're separated by a space.

Examples:

  • sizes="16x16" (1 size)
  • sizes="16x16 32x32 64x64" (3 different sizes)
  • sizes="any" (any size)

Global Attributes

The following attributes are standard across all HTML 5 tags (although the tabindex attribute does not apply to dialog elements).

For a full explanation of these attributes, see HTML 5 global attributes.

Event Handler Content Attributes

Event handler content attributes enable you to invoke a script from within your HTML. The script is invoked when a certain "event" occurs. Each event handler content attribute deals with a different event.

For a full list of event handlers, see HTML 5 event handler content attributes.