How to display current and parent category of a post (WordPress snippet)

When building custom WordPress themes, you often need to display not just the current category, but also its parent category (for breadcrumb navigation or hierarchical menus).

WordPress stores categories in a hierarchical structure, but get_the_category() returns a flat array. Here’s how to extract the hierarchy.

Method: Get_the_category() + parent check

Here’s a ready-made function you can paste into functions.php:

function wppoland_get_category_hierarchy() {
    $categories = get_the_category();
    
    if ( empty( $categories ) ) {
        return false;
    }
    
    // Get the first category
    $category = $categories[0];
    
    $output = '';
    
    // If category has a parent
    if ( $category->parent ) {
        $parent = get_category( $category->parent );
        $output .= '<a href="' . esc_url( get_category_link( $parent->term_id ) ) . '">' . esc_html( $parent->name ) . '</a> &raquo; ';
    }
    
    // Current category
    $output .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '">' . esc_html( $category->name ) . '</a>';
    
    return $output;
}

Usage IN template

<?php
$hierarchy = wppoland_get_category_hierarchy();
if ( $hierarchy ) {
    echo '<div class="category-breadcrumb">' . $hierarchy . '</div>';
}
?>

This will output something like: Technology » WordPress

Alternative: Full breadcrumb trail

If you need the complete hierarchy (grandparent, parent, child), use this recursive approach:

function wppoland_get_full_category_trail( $category_id ) {
    $trail = array();
    
    while ( $category_id ) {
        $category = get_category( $category_id );
        array_unshift( $trail, $category );
        $category_id = $category->parent;
    }
    
    $output = '';
    foreach ( $trail as $cat ) {
        $output .= '<a href="' . esc_url( get_category_link( $cat->term_id ) ) . '">' . esc_html( $cat->name ) . '</a> &raquo; ';
    }
    
    return rtrim( $output, ' &raquo; ' );
}

This solution is clean, efficient, and handles multi-level category hierarchies properly.