Woo Custom Fields

WooCommerce Custom Fields & Attributes

Before writing code

Fetch live docs:

1. Web-search site:developer.woocommerce.com product data custom fields for product custom fields guide
2. Web-search site:developer.wordpress.org plugins metadata for WordPress metadata API
3. Web-search woocommerce custom product attributes programmatically for attribute creation

Product Attributes

Global Attributes

Defined in WooCommerce > Attributes — shared across all products:

• Stored as custom taxonomies: pa_{attribute_slug} (e.g., pa_color, pa_size)
• Terms are the possible values (Red, Blue, Small, Large)
• Can be used for filtering, variations, and layered navigation
• Managed via wc_create_attribute(), wc_update_attribute(), wc_delete_attribute()

Custom (Local) Product Attributes

Per-product attributes — not global taxonomies:

• Stored in product meta as part of _product_attributes array
• Visible on the product page under "Additional Information" tab
• Set via $product->set_attributes() with WC_Product_Attribute objects

Setting Attributes Programmatically

Create WC_Product_Attribute objects:

• set_id() — 0 for custom attributes, taxonomy ID for global
• set_name() — taxonomy name (pa_color) or custom label
• set_options() — array of term IDs (global) or string values (custom)
• set_visible() — show on product page
• set_variation() — used for variations

Product Meta

Core Meta Keys

Custom Meta

• $product->update_meta_data( '_my_custom_field', $value ) then $product->save()
• $product->get_meta( '_my_custom_field' ) — retrieve value
• Prefix custom keys with _ to hide from the Custom Fields meta box

Adding Product Edit Fields

Use hooks to add fields to the product edit screen:

• woocommerce_product_options_general_product_data — General tab
• woocommerce_product_options_inventory_product_data — Inventory tab
• woocommerce_product_options_shipping_product_data — Shipping tab
• woocommerce_product_options_advanced — Advanced tab
• Save with: woocommerce_process_product_meta action

Field Rendering Functions

• woocommerce_wp_text_input( $args ) — text input
• woocommerce_wp_textarea_input( $args ) — textarea
• woocommerce_wp_select( $args ) — dropdown select
• woocommerce_wp_checkbox( $args ) — checkbox
• woocommerce_wp_hidden_input( $args ) — hidden field

Custom Product Tabs

Adding to Product Page

Filter woocommerce_product_tabs to add, remove, or reorder tabs:

• Return array with title, priority, callback keys
• Remove default tabs by unsetting keys: description, additional_information, reviews

Adding to Product Edit (Admin)

Filter woocommerce_product_data_tabs to add tabs in the product editor:

• Return array with label, target, class, priority
• Render panel content via woocommerce_product_data_panels action

Order Meta

• $order->update_meta_data( '_my_field', $value ) then $order->save()
• $order->get_meta( '_my_field' ) — retrieve value
• HPOS-compatible: always use CRUD methods, never update_post_meta()

Customer Meta

• $customer->update_meta_data() / $customer->get_meta() via WC_Customer
• Or update_user_meta() / get_user_meta() for WordPress user meta

Custom Taxonomies

Registering Custom Taxonomies

Use register_taxonomy() on init hook:

• Associate with product post type for product classification
• Set show_in_rest for REST API / block editor support
• Hierarchical (like categories) or flat (like tags)

Best Practices

• Use global attributes for values shared across products (color, size, brand)
• Use custom meta for product-specific data not used in filtering
• Prefix custom meta keys with underscore to hide from the generic meta box
• Always use CRUD methods (update_meta_data / get_meta) for HPOS compatibility
• Sanitize all input before saving: sanitize_text_field(), wc_clean(), absint()
• Escape all output: esc_html(), esc_attr(), wp_kses_post()

Fetch the WooCommerce product data and metadata documentation for exact hook names, field function signatures, and attribute API before implementing.