Using WordPress ‘is_main_blog()’ PHP function

The is_main_blog() WordPress PHP function is a deprecated function used to determine if the current site is the main site. You should use is_main_site() instead.

Usage

if (is_main_blog()) {
    // Do something if the current site is the main site
}

Parameters

None

More information

See WordPress Developer Resources: is_main_blog

This function is deprecated. Use is_main_site() instead.

Examples

Display a message on the main site

This example checks if the current site is the main site and displays a message.

if (is_main_blog()) {
    echo 'This is the main site!';
}

Redirect users to the main site

This example redirects users to the main site if they’re not already there.

if (!is_main_blog()) {
    wp_redirect(get_main_site_url());
    exit;
}

This example shows how to display a specific widget only on the main site.

if (is_main_blog()) {
    dynamic_sidebar('main-site-sidebar');
}

Load a specific stylesheet for the main site

This example shows how to enqueue a specific stylesheet only for the main site.

function load_main_site_stylesheet() {
    if (is_main_blog()) {
        wp_enqueue_style('main-site-style', get_template_directory_uri() . '/main-site.css');
    }
}
add_action('wp_enqueue_scripts', 'load_main_site_stylesheet');

This example shows how to display a specific navigation menu only on the main site.

function display_main_site_menu() {
    if (is_main_blog()) {
        wp_nav_menu(array('theme_location' => 'main-site-menu'));
    } else {
        wp_nav_menu(array('theme_location' => 'other-sites-menu'));
    }
}
display_main_site_menu();