# Expose Custom Product Fields in the WooCommerce REST API

> Adds the product meta fields you list to WooCommerce REST API product responses as a tidy "custom_fields" object, and lets API clients update them.

- Type: PHP
- Runs: Run everywhere
- Category: [WooCommerce](https://wpide.com/library/category/woocommerce/)
- Requires: WooCommerce
- Tags: woocommerce, rest-api, products, integrations
- Author: WPIDE Team
- Installs: 0
- Updated: 2026-10-28
- Page: https://wpide.com/library/woo-rest-product-custom-meta/

## Code

```php
$wpide_rest_product_meta = array( '_wpide_subtitle', '_wpide_cost', '_wpide_unit_label' ); // Meta keys to expose.

add_filter( 'woocommerce_rest_prepare_product_object', function ( $response, $product ) use ( $wpide_rest_product_meta ) {
    $fields = array();

    foreach ( $wpide_rest_product_meta as $key ) {
        $fields[ ltrim( $key, '_' ) ] = $product->get_meta( $key );
    }

    $response->data['custom_fields'] = $fields;

    return $response;
}, 10, 2 );

add_action( 'woocommerce_rest_insert_product_object', function ( $product, $request ) use ( $wpide_rest_product_meta ) {
    $incoming = $request->get_param( 'custom_fields' );

    if ( ! is_array( $incoming ) ) {
        return;
    }

    foreach ( $wpide_rest_product_meta as $key ) {
        $name = ltrim( $key, '_' );

        if ( array_key_exists( $name, $incoming ) && is_scalar( $incoming[ $name ] ) ) {
            $product->update_meta_data( $key, sanitize_text_field( (string) $incoming[ $name ] ) );
        }
    }

    $product->save_meta_data();
}, 10, 2 );
```

## Notes

Only the keys you list are exposed or writable, and API clients still need WooCommerce API keys with the right access.

## How to use it

Install the free WPIDE plugin (https://wordpress.org/plugins/wpide/), find "Expose Custom Product Fields in the WooCommerce REST API" in its snippet library and add it in one click; or create a new PHP snippet in WPIDE (or any code snippets plugin) and paste the code above. More snippets: https://wpide.com/library/