Skip to main content

Update cart item quantity

Change the quantity of an existing line item in the cart.

Mutation​

mutation UpdateCartItem($cartId: String!, $itemId: String!, $quantity: Int!) {
  cartUpdateItem(
    id: $cartId
    itemId: $itemId
    input: { quantity: $quantity }
  ) {
    items {
      itemId
      productId
      quantity
      price
      priceNet
      totalPrice
      totalPriceNet
    }
    total {
      subTotal
      totalGross
      totalNet
    }
  }
}

Variables​

{
  "cartId": "019c77b7-565f-7ea0-8660-42bc63a7f728",
  "itemId": "019c77b7-72a0-75fe-8a20-b98927d76652",
  "quantity": 5
}

Response​

{
  "data": {
    "cartUpdateItem": {
      "items": [
        {
          "itemId": "019c77b7-72a0-75fe-8a20-b98927d76652",
          "productId": 25,
          "quantity": 5,
          "price": 1595.04,
          "priceNet": 1929.99,
          "totalPrice": 7975.20,
          "totalPriceNet": 9649.99
        }
      ],
      "total": {
        "subTotal": 7975.20,
        "totalGross": 8310.20,
        "totalNet": 10055.34
      }
    }
  }
}

How it works​

The itemId is a top-level argument, not part of the input object. Setting quantity to 0 does not remove the item — use cartDeleteItem for that. The response returns the full updated cart so you can refresh totals in one round trip. Products with minimumQuantity or purchaseUnit constraints will reject invalid quantities.

See also​