Gist to delete Gmail Labels created by the Gmail plugin called Philterit.

remove_philterit_for_gmail_labels.php

<?php

  // delete all labels / folders created by Philterit for Gmail
	//
	//	- Philterit is an app that organizes your gmail by applying labels
	//		to emails for all the brands that email you.  Philterit shut down,
	//		but the labels ( thousands of them ) remained in my Gmail account.
	//
	//	- this app removes them all in bulk.
	//
	//	- use:
	//	
	//		- update $user and $pass with your gmail username and password
	//		- execute this app from the command line ( eg. php remove_philterit_for_gmail_labels.php )
	//		
	//		*** you may have to install the php imap module
	//			- if you use yum, this can probably be accomplished by executing ( sudo yum install php-imap )
	//
	//		*** this can take hours to run depending on how many labels Philterit created
	//			- roughly two seconds per label ( eg. 3,000 labels will take ~1.5hrs to process )
	//

    // your gmail credentials
	$user = 'YOUR-GMAIL-ADDRESS';
	$pass = 'YOUR-GMAIL-PASSWORD';
	$host = '{imap.gmail.com:993/imap/ssl}';

    // try to connect
    $Inbox = imap_open( $host . 'INBOX', $user, $pass ) or die( 'Imap connection to Gmail Failed: ' . imap_last_error() );
		
	// get all folders ( gmail calls most of these labels )
    $folders = imap_list( $Inbox, $host, '*' );

	// loop through folders and delete all Philterit brand labels
    $i = 0;
    $total = count( $folders );
    foreach( $folders as $folder ) {
		if( strpos( $folder, '&8HY-Brand/' ) ) {
			$i++;
			if( imap_deletemailbox( $Inbox, $folder ) )
				echo "$i of $total) deleted: " . $folder . "\n";
		}
	}

	echo "\n\nPhilterit labels have been removed!!!";

?>