Create item-scoped custom parameters

The items array in ecommerce events lets you describe the products or services on your ecommerce website. Google provides a list of required and recommended parameters to include in the items array.

In addition to these parameters, you can include up to 27 custom parameters in the items array. These custom parameters are called custom item-scoped parameters and they let you capture data that's useful to your business. Of these 27 custom item parameters, you can configure:

• 10 item-scoped custom dimensions for standard properties
• 25 item-scoped custom dimensions for Analytics 360 properties

Make sure to review the list of required and recommended parameters before creating your own item-scoped custom parameters.

Add an item-scoped custom parameter

To add an item-scoped custom parameter, include the parameter in the items array. For example, to capture whether a product is in stock, you can add the following in_stock custom parameter to the event:

items: [
  {
    item_id: "SKU_12345",
    item_name: "Stan and Friends Tee",
    affiliation: "Google Merchandise Store",
    coupon: "SUMMER_FUN",
    discount: 2.22,
    index: 0,
    item_brand: "Google",
    item_category: "Apparel",
    item_category2: "Adult",
    item_category3: "Shirts",
    item_category4: "Crew",
    item_category5: "Short sleeve",
    item_list_id: "related_products",
    item_list_name: "Related Products",
    item_variant: "green",
    in_stock: true, // The item-scoped custom parameter "in_stock"
    location_id: "ChIJIQBpAG2ahYAR_6128GcTUEo",
    price: 10.01,
    quantity: 3
  }
]

Note that these steps apply to both gtag.js and Google Tag Manager implementations.

Next steps

To analyze item-scoped custom parameters, you must create an item-scoped custom dimension. For information about how to set up the item-scoped custom dimension, see Custom dimensions and metrics.