base: The Document Base URL element

The <base> HTML element specifies the base URL to use for all relative URLs in a document. There can be only one <base> element in a document. It is a child of the head element.

Attributes

Specific attributes

Required attributes

href is the base URL to be used throughout the document for relative URLs. Absolute and relative URLs are allowed. data: and javascript: URLs are not allowed.

Allowed attributes

target contains a keyword or author-defined name of the default browsing context to show the results of navigation from a or form elements without explicit target attributes. The following keywords have special meanings:

• _self (default): Show the result in the current browsing context.
• _blank: Show the result in a new, unnamed browsing context.
• parent: Show the result in the parent browsing context of the current one, if the current page is inside a frame. If there is no parent, acts the same as self.
• top: Show the result in the topmost browsing context (the browsing context that is an ancestor of the current one and has no parent). If there is no parent, acts the same as self.

Global attributes

accesskey Specifies a keyboard shortcut to activate or focus an element.

aria-* Defines accessibility properties and states for assistive technologies.

class Specifies one or more CSS class names for styling the element.

data-* Stores custom data private to the page or application.

dir Sets the text direction (left-to-right, right-to-left, or auto).

hidden Hides the element from display and assistive technologies.

id Defines a unique identifier for the element within the document.

inputmode Hints which virtual keyboard type to display on mobile devices.

itemid Provides a global identifier for microdata items.

itemprop Defines a property name-value pair for microdata.

itemref Associates properties with an item via element IDs for microdata.

itemscope Creates a new microdata item container.

itemtype Specifies the vocabulary URL for microdata items (like Schema.org).

lang Specifies the primary language of the element’s content.

nonce Provides a cryptographic nonce for Content Security Policy.

role Defines the element’s semantic role for accessibility.

tabindex Controls keyboard navigation order and focusability.

title Provides advisory information displayed as a tooltip.

Example

<base target="_top" href="https://example.com/" />