Retrieve the amount of comments a post has.

Signature

get_comments_number( $post_id = 0 )
post_id
 (int|WP_Post) Post ID or WP_Post object. Default current post.
Default: 0

Return

(int) The number of comments a post has.

Source

function get_comments_number( $post_id = 0 ) {
	$post_id = absint( $post_id );

	if ( !$post_id )
		$post_id = get_the_ID();

	$post = get_post($post_id);
	if ( ! isset($post->comment_count) )
		$count = 0;
	else
		$count = $post->comment_count;

	/**
	 * Filter the returned comment count for a post.
	 *
	 * @since 1.5.0
	 *
	 * @param int         $count   Nnumber of comments a post has.
	 * @param int|WP_Post $post_id Post ID or WP_Post object.
	 */
	return apply_filters( 'get_comments_number', $count, $post_id );
}
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