Introduction

WordPress-specific global variables are used throughout WordPress code for various reasons. Almost all data that WordPress generates can be found in a global variable.

Note that it’s best to use the appropriate API functions when available, instead of modifying globals directly.

To access a global variable in your code, you first need to globalize the variable with global $variable;.

Accessing other globals besides the ones listed below is not recommended.

Inside the Loop variables

While inside the loop, these globals are set, containing information about the current post being processed.

• $post (WP_Post): The post object for the current post. Object described in WP_Post Class Reference.
• $posts: Used by some core functions, not to be mistaken for $query->$posts.
• $authordata (WP_User): The author object for the current post. Object described in WP_User Class Reference.
• $currentday (string): Day that the current post was published.
• $currentmonth (string): Month that the curent post was published.
• $page (int): The page of the current post being viewed. Specified by the query var page.
• $pages (array): The content of the pages of the current post. Each page elements contains part of the content separated by the <!--nextpage--> tag.
• $multipage (boolean): Flag to know if the current post has multiple pages or not. Returns true if the post has multiple pages, related to $pages.
• $more (boolean): Flag to know if WordPress should enforce the <!--more--> tag for the current post. WordPress will not enforce the more tag if true.
• $numpages (int): Returns the number of pages in the post, related to $pages.

Browser Detection Booleans

These globals store data about which browser the user is on.

• $is_iphone (boolean): iPhone Safari
• $is_chrome (boolean): Google Chrome
• $is_safari (boolean): Safari
• $is_NS4 (boolean): Netscape 4
• $is_opera (boolean): Opera
• $is_macIE (boolean): Mac Internet Explorer
• $is_winIE (boolean): Windows Internet Explorer
• $is_gecko (boolean): FireFox
• $is_lynx (boolean): Lynx
• $is_IE (boolean): Internet Explorer
• $is_edge (boolean): Microsoft Edge

Web Server Detection Booleans

These globals store data about which web server WordPress is running on.

• $is_apache (boolean): Apache HTTP Server
• $is_IIS (boolean): Microsoft Internet Information Services (IIS)
• $is_iis7 (boolean): Microsoft Internet Information Services (IIS) v7.x
• $is_nginx (boolean): Nginx web server

Version Variables

• $wp_version (string): The installed version of WordPress
• $wp_db_version (int): The version number of the database
• $tinymce_version (string): The installed version of TinyMCE
• $manifest_version (string): The cache manifest version
• $required_php_version (string): The version of PHP this install of WordPress requires
• $required_mysql_version (string): The version of MySQL this install of WordPress requires

Misc

• $super_admins (array): An array of user IDs that should be granted super admin privileges (multisite). This global is only set by the site owner (e.g., in wp-config.php), and contains an array of IDs of users who should have super admin privileges. If set it will override the list of super admins in the database.
• $wp_query (object): The global instance of the WP_Query class.
• $wp_rewrite (object): The global instance of the WP_Rewrite class.
• $wp (object): The global instance of the WP environment setup class.
• $wpdb (object): The global instance of the wpdb class.
• $wp_locale (object): The global instance of the WP_Locale class.
• $wp_admin_bar (object): The global instance of the WP_Admin_Bar class.
• $wp_roles (object): The global instance of the WP_Roles class.
• $wp_meta_boxes (array): Object containing all registered metaboxes, including their id’s, args, callback functions and title for all post types including custom.
• $wp_registered_sidebars (array)
• $wp_registered_widgets (array)
• $wp_registered_widget_controls (array)
• $wp_registered_widget_updates (array)

Admin Globals

• $pagenow (string): Used in wp-admin. 
  See also get_current_screen() for the WordPress Admin Screen API.
• $post_type (string): Used in wp-admin
• $allowedposttags (array)
• $allowedtags (array)
• $menu (array)