I wish to change/remove parts of the automatic post class function that's built in to wordpress, lets say when i make a post, the html code generated looks like this:

<div id="post-106" class="contentmain fullwidth post-106 post type-post status-publish format-standard has-post-thumbnail hentry category-test category-test2 category-test3 category-test4 tag-testingtags1 tag-testingtags2 tag-testingtags3"> 

I wish to remove tags from being in this auto generated code (the tag-testingtags1,2,3), i cannot find which function in wordpress generates the code, anyone care to point me in the right direction? If it is a core file is there a simple way to exclude tags from being inserted into the code using some kind of filter hook in functions.php so i don't have to modify wp core files?

2 Answers 2


post_class() is a wrapper around get_post_class().

Try the following hook post_class which is fired from get_post_class() within wp-includes/post-template.php:

add_filter('post_class', 'filter_post_class', 10, 3);

function filter_post_class($classes, $class, $post_id) {

    $temp = implode(' ', $classes); 
    $temp = preg_replace('/\s\btag\-\w*\b/i', '', $temp);

    return explode(' ', $temp);


Alternatively (RECOMMENED):

add_filter('post_class', 'filter_post_class', 10, 3);

function filter_post_class($classes, $class, $post_id) {

    $classes = array_filter($classes, function($class_name){
       // use !== 0 to ensure we match tag- at begining of string
       return strpos($class_name, 'tag-') !== 0;

    return $classes;


Another alternative method, although potentially with risks, is to:

add_filter('get_the_tags', 'filter_get_the_tags');

function filter_get_the_tags() {

    return array();


Although with this approach some conditional logic should be considered within the callback.

I say that for the latter because the only other function (in terms of core WP) that calls get_the_tags() is wp-includes/feed.php and inparticular get_the_category_rss().

  • 1
    Second alternative seems to be working best in my tests, the first alternative only filters out the tag- part, thanks very much for the elaborate response! Mar 23, 2016 at 8:18
  • @SandraJohansson no problem... the second approach is recommened since it is already an array; interesting that the first approach does not work for you though. I tested the regex fine on my end... never the less, glad you have it sorted either way.
    – Adam
    Mar 23, 2016 at 8:30
  • What if i want to change the article html tag Jan 21, 2022 at 9:21

You can use the post_class filter to modify the output of post classes:

add_filter( 'post_class', 'cyb_post_class' );
function cyb_post_class( $classes ) {

    // Modify the array $classes as you wish
    // For example: remove tag-testingtags1 class
    unset( $classes['tag-testingtags1'] );

    return $classes;

The classes with names starting with tag- are generated form the tags associated with the post (post tag taxonomy from core). If you want to auto-remove those classes:

add_filter( 'post_class', 'cyb_post_class', 10, 3 );
function cyb_post_class( $classes, $class, $post_id ) {

    // Get all the tags associated with the post
    $tags = get_the_tags( $post_id );
    if( ! is_wp_error( $tags ) ) {
        foreach( $tags as $tag ) {
            if( isset( $classes['tag-' . $tag->slug] ) ) {
                 unset( $classes['tag-' . $tag->slug] );

    return $classes;

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.