How to Create WordPress REST API Using PHP

• Tech Area
• Last updated on: January 19, 2026

WordPress REST API allows developers to connect WordPress with mobile apps, React, Vue, or external PHP applications. It is one of the most trending WordPress development topics because modern websites rely heavily on APIs.

In this tutorial, you’ll learn how to create and use WordPress REST API using PHP, step by step, with real examples.

What Is WordPress REST API?

The WordPress REST API enables you to:

1. Access WordPress data in JSON format

2. Create custom endpoints

3. Perform CRUD operations (Create, Read, Update, Delete)

4. Connect WordPress with external apps

Example API URL:

https://example.com/wp-json/wp/v2/posts

Why WordPress REST API Is Trending

✔ Used in headless WordPress
✔ Required for React & mobile apps
✔ Faster than traditional PHP templates
✔ Essential for modern WordPress development
✔ Widely used in SaaS & dashboards

Create Custom REST API Endpoint in WordPress

Step 1: Add Code in functions.php

add_action('rest_api_init', function () {
    register_rest_route('custom-api/v1', '/posts', array(
        'methods'  => 'GET',
        'callback' => 'get_custom_posts_api',
    ));
});

Step 2: Create API Callback Function

function get_custom_posts_api() {

    $args = array(
        'post_type'      => 'post',
        'posts_per_page' => 5
    );

    $query = new WP_Query($args);
    $posts = array();

    if ($query->have_posts()) {
        while ($query->have_posts()) {
            $query->the_post();

            $posts[] = array(
                'id'    => get_the_ID(),
                'title' => get_the_title(),
                'link'  => get_permalink(),
            );
        }
        wp_reset_postdata();
    }

    return rest_ensure_response($posts);
}

Test Your REST API Endpoint

Open browser:

https://yourwebsite.com/wp-json/custom-api/v1/posts

Output (JSON):

[
  {
    "id": 12,
    "title": "Sample Post",
    "link": "https://yourwebsite.com/sample-post"
  }
]

Create REST API Using PHP (POST Request)

register_rest_route('custom-api/v1', '/add-post', array(
    'methods' => 'POST',
    'callback' => 'create_post_api'
));

function create_post_api($request) {

    $post_id = wp_insert_post(array(
        'post_title'   => sanitize_text_field($request['title']),
        'post_content' => sanitize_textarea_field($request['content']),
        'post_status'  => 'publish'
    ));

    return array(
        'success' => true,
        'post_id' => $post_id
    );
}

Security Best Practices

✔ Use authentication (JWT / Application Passwords)
✔ Sanitize & validate input
✔ Restrict permissions using permission_callback
✔ Avoid exposing sensitive data

Where WordPress REST API Is Used

1. Headless WordPress websites

2. Mobile apps (Android / iOS)

3. React / Vue / Next.js apps

4. External PHP dashboards

5. Automation systems

Conclusion

Creating a WordPress REST API using PHP is an essential skill for modern developers. It allows you to build scalable, fast, and flexible applications while keeping WordPress as a powerful backend.