'active', 'welcome' => '', ) ); $image_sizes = wp_get_registered_image_subsizes(); $thumbnail_size = $image_sizes['thumbnail']['width'] . 'x' . $image_sizes['thumbnail']['height'] . ' px'; $registered_sizes = ''; foreach ( $image_sizes as $name => $size ) { $registered_sizes .= $name . ', '; } $registered_sizes = trim( $registered_sizes, ', ' ); $registered_sizes .= '.'; ?>