HTML <link> Tag

The HTML <link> tag represents a link to an external resource.

The <link> tag is often 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 can be used to create 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.

Syntax

The <link> tag is typically written as <link rel="" href=""> (no end tag). The rel attribute specifies the relationship between the document containing the hyperlink and the destination resource. The href attribute specifies the address of the hyperlink. See below under "Template" for other attributes that can be used with the <link> tag.

Like this:

Examples

Basic tag usage

The <link> tag can be placed either whereever metadata is expected or in a <noscript> element that is a child of a <head> element.

Here is a typical usage of the <link> element, which links to an external style sheet.

Attributes

Attributes can be added to an HTML element to provide more information about how the element should appear or behave.

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

The <link> element accepts the following attributes.

Element-Specific Attributes

This table shows the attributes that are specific to the <link> tag/element.

Attribute Description

href Specifies the URL of the resource document.

crossorigin

This 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:

Value	Description
anonymous	Cross-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-credentials	Cross-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.

hreflang Language code of the destination URL. Purely advisory. The value must be a valid RFC 3066 language code.

media

Specifies 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].

rel

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

Possible values:

Value	Description
alternate	Gives 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">`
author	Gives a link to the current document's author
help	Provides a link to context-sensitive help.
icon	Imports an icon to represent the current document.
license	Indicates that the main content of the current document is covered by the copyright license described by the referenced document.
next	Indicates that the current document is a part of a series, and that the next document in the series is the referenced document.
prefetch	Specifies that the target resource should be preemptively cached.
prev	Indicates that the current document is a part of a series, and that the previous document in the series is the referenced document.
search	Gives a link to a resource that can be used to search through the current document and its related pages.
stylesheet	Imports an external stylesheet.

type The MIME type of content at the link destination. Purely advisory.

sizes

Specifies 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 HTML5 elements. Therefore, you can use these attributes with the <link> tag , as well as with all other HTML tags.

accesskey
class
contenteditable
contextmenu
dir
draggable
dropzone
hidden
id
inert
itemid
itemprop
itemref
itemscope
itemtype
lang
spellcheck
style
tabindex
title
translate

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.

Below are the standard HTML5 event handler content attributes.

Again, you can use any of these with the <link> element, as well as any other HTML5 element.

onabort
oncancel
onblur
oncanplay
oncanplaythrough
onchange
onclick
oncontextmenu
ondblclick
ondrag
ondragend
ondragenter
ondragexit
ondragleave
ondragover
ondragstart
ondrop
ondurationchange
onemptied
onended
onerror
onfocus
onformchange
onforminput
oninput
oninvalid
onkeydown
onkeypress
onkeyup
onload
onloadeddata
onloadedmetadata
onloadstart
onmousedown
onmousemove
onmouseout
onmouseover
onmouseup
onmousewheel
onpause
onplay
onplaying
onprogress
onratechange
onreadystatechange
onscroll
onseeked
onseeking
onselect
onshow
onstalled
onsubmit
onsuspend
ontimeupdate
onvolumechange
onwaiting

For a full explanation of these attributes, see HTML 5 event handler content attributes.

Differences Between HTML 4 & HTML 5

HTML5 does not support the following attributes (that were supported in HTML 4):

rev
target
charset

HTML5 introduced the following attributes:

crossorigin
sizes

To see more detail on the two versions see HTML5 <link> Tag and HTML4 <link> Tag. Also check out the links to the official specifications below.

Template

Here's a template for the <link> tag with all available attributes for the tag (based on HTML5). These are grouped into attribute types, each type separated by a space. In many cases, you will probably only need one or two (if any) attributes. Simply remove the attributes you don't need.

For more information on attributes for this tag, see HTML5 <link> Tag and HTML4 <link> Tag.

* The title attribute has special semantics on the <link> element. If used, it defines alternative style sheet sets.

Also, the title attribute on <link> elements differs from the global title attribute of most other elements in that a <link> element without a title does not inherit the title of the parent element: it simply has no title.

Tag Details

For more details about the <link> tag, see HTML5 <link> Tag and HTML4 <link> Tag.

Specifications

Here are the official specifications for the <link> element.

HTML5 Specification (W3C)
HTML Living Standard (WHATWG)
Current W3C Draft (the next version that is currently being worked on)
HTML 4 (W3C)

What's the Difference?

W3C creates "snapshot" specifications that don't change once defined. So the HTML5 specification won't change once it becomes an official recommendation. WHATWG on the other hand, develops a "living standard" that is updated on a regular basis. In general, you will probably find that the HTML living standard will be more closely aligned to the current W3C draft than to the HTML5 specification.

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