// this function initializes the iframe elements function add_iframe($initArray) { $initArray['extended_valid_elements'] = "iframe[id|class|title|style|align|frameborder|height|longdesc|marginheight|marginwidth|name|scrolling|src|width]"; return $initArray; } // this function alters the way the WordPress editor filters your code add_filter('tiny_mce_before_init', 'add_iframe');