Admin Toolbar or Admin Bar is a part of WordPress admin dashboard or front end which i personally don’t like much. Some of the options provided in the admin bar are already present in the sidebar menu. So it’s not a good idea to put same content to the dashboard twice.

Here is the complete list of code snippet which helps you to customize admin bar for you. Place the code in theme function file functions.php.

1. Completely Removing Admin Bar from Admin Dashboard Page

Below code will disable the admin bar from admin dashboard. Copy and paste the code to your functions.php. Usually before the ?> in your function file.

//Completely Removes Admin Bar from Admin Page
remove_action( 'admin_footer', 'wp_admin_bar_render', 1000 ); // For admin page

// CSS override for the admin page
function remove_admin_bar_style_backend() {
echo '';
    }
add_filter('admin_head','remove_admin_bar_style_backend');

2. Completely Removing Admin Bar from Front End

Below code snippet removes admin bar/ toolbar from front end of your site.

//Completely Removes Admin Bar from Front End Site
remove_action( 'wp_footer', 'wp_admin_bar_render', 1000 ); // For front end

// CSS override for the frontend
function remove_admin_bar_style_frontend() {
echo '';
    }
add_filter('wp_head','remove_admin_bar_style_frontend', 99);

Thanks to TutsPlus

3. Customizing Admin Bar Links One By One

Please modify according to your need and use the below code if you want to retain some of the links. Please go through each and every comments which explains you which link removes after inserting the line of code. Just comment out or delete the line if you want to retain the link in admin bar.

function blgs_rnb_remove_admin_bar() {
    global $wp_admin_bar;

	//Remove WordPress Logo Menu Items
    $wp_admin_bar->remove_menu('wp-logo'); // Completely Removes WP Logo, Below are the individual items
    $wp_admin_bar->remove_menu('about');   // 'About WordPress'
    $wp_admin_bar->remove_menu('wporg');   // 'WordPress.org'
    $wp_admin_bar->remove_menu('documentation');  // 'Documentation'
    $wp_admin_bar->remove_menu('support-forums');  // 'Support Forums'
    $wp_admin_bar->remove_menu('feedback');       // 'Feedback'

    //Remove Site Name Items
	$wp_admin_bar->remove_menu('site-name'); // Completely Removes Site Name from Dashboar and Front End Admin Bar, Below are the individual items
	$wp_admin_bar->remove_menu('view-site'); // 'Visit Site'

	$wp_admin_bar->remove_menu('dashboard'); // 'Dashboard' Link, Only Front End
	$wp_admin_bar->remove_menu('themes'); // 'Themes' Link, Only Front End
	$wp_admin_bar->remove_menu('widgets'); // 'Widgets' Link, Only Front End
	$wp_admin_bar->remove_menu('menus'); // 'Menus' Link, Only Front End

	// Remove Comments Bubble
	$wp_admin_bar->remove_menu('comments');

	//Remove Update Link if theme/plugin/core updates are available
	$wp_admin_bar->remove_menu('updates');

	//Remove '+ New' Menu Items
	$wp_admin_bar->remove_menu('new-content'); // Completely Removes '+ New' from Dashboar and Front End Admin Bar, Below are the individual items
	$wp_admin_bar->remove_menu('new-post');   // 'Post' Link
	$wp_admin_bar->remove_menu('new-media');   // 'Media' Link
	$wp_admin_bar->remove_menu('new-link');   // 'Link' Link
	$wp_admin_bar->remove_menu('new-page');   // 'Page' Link
	$wp_admin_bar->remove_menu('new-user');   // 'User' Link

	// Remove 'Howdy, username' Menu Items
	$wp_admin_bar->remove_menu('my-account');  // Completely Removes 'Howdy, username' and Menu Items
	$wp_admin_bar->remove_menu('user-actions');  // Completely Removes Submenu Items Only
	$wp_admin_bar->remove_menu('user-info'); // 'username' which links to profile page
    $wp_admin_bar->remove_menu('edit-profile');  // 'Edit My Profile' Link
	$wp_admin_bar->remove_menu('logout');  // 'Log Out' Link

}
add_action( 'wp_before_admin_bar_render', 'blgs_rnb_remove_admin_bar' );