How to get Category Id from Post Id ?

Question

I need to get any post category id from the post id(Not for current) Post. How can i ?

Thanks

Answer 1

You can try this code for getting category id from post id:

global $post;
$category_detail=get_the_category( $post->ID );

Answer 2

Take a look at wp_get_post_categories function. It returns an array of categories' ID for specific post.

$post_categories = wp_get_post_categories( $post_id );