Google Merchant Center

Item Group ID Attribute: The Right Way To Present Variants to Customers

0 · by Dennis Moons · Updated on 26 April 2023

When feed inventories have a lot of variants of the same product, advertisers need a way to present all available options to customers while keeping the ad format clean and easy to navigate.

Google introduced the item_group_id as a solution.

In this piece, we’ll discuss the item group ID attribute and explain what it is, how it works in Google Shopping, what are its formatting requirements, and ways to solve feed issues with this attribute.

Let’s dive straight in.

This article is part of our Google Data Feed hub.

What Is the Item Group ID Attribute in the Product Feed?

Item_group_id allows advertisers to group variants of the same product. This attribute is usually used for apparel and product variants that differ by product details like color, size, age group, gender, pattern, theme, or material.

However, it can also be used for other items that have different variants based on flavor, scent, capacity count, etc.

The item group ID attribute can be used only for variants of the same product, and not with complementary products (i.e. all items in the item_group_id should be shoes, not shoes and socks).

Item_group_id is not the same as product ID. For example, a jacket in three sizes (S, M, and L) and three colors (black, brown, and green) will have 9 variants, each with its own product ID, but all 9 items will be grouped under the same item group ID (which can be named “jacket” in your feed).

We’ll delve deeper into all aspects of the attribute as we go along.

Is the Item Group ID Attribute Required?

Yes, item_group_id is required for both free listings and Google Shopping. However, for Google Shopping, it’s required only for stores that target these countries:

  • Brazil
  • France
  • Germany
  • Japan
  • United Kingdom
  • United States

How Is the Item Group ID Attribute Used in Google Shopping?

If you put all variations of a product under the same item_group_id, they will be shown to customers as a group. This attribute is what ties them all together.

There are a lot of benefits to using item_group_id. When each product is shown separately, customers might not be aware that the product variant they need is available at the store.

Having a group of product variants appear together is likely to improve click-through rates, because users can easily access variations. For some categories of products, like clothing, this can affect conversions because users often prefer a specific color or pattern of the item.

Let’s check the formatting requirements for item_group_id.

Options for Item Group ID

Values for item_group_id can contain alphanumeric characters, underscores, and dashes (the limit is up to 50 Unicode characters). Dashes and underscores come in handy for differentiating product variants while keeping the same parent SKU for all items in the group.

In text feeds, you can simply enter the value for item_group_id, for instance “ABCDE123.”

In XML feeds, you need to provide a tag before and after the value: <g:item_group_id>ABCDE123</g:item_group_id>.

Let’s take a look at methods to add this attribute.

How To Add Item Group ID to Your Product Feed

There are two ways to create item_group_id for items in your feed: through a shopping platform or directly in your feed.

If you use a data feed tool, you can configure item group IDs and they will be automatically shared with your feed.

Within Google Merchant center, you can make the changes directly with feed rules or with supplemental feeds. When you use feed rules, first single out products based on a criteria (for example, all items have the same word in their product titles) and then you can change this attribute.

With supplemental feeds, you need to provide a csv. file containing product IDs in one column and values for item_group_id in another.

Let’s explain the differences between product IDs and item group IDs.

Item Group ID vs Unique Products

Product ID, or the product ID attribute, serves to uniquely identify a product. Google automatically assigns this ID and each item has one. So, if you have a product with multiple variants, each variant will have a unique product ID.

The item group ID puts all variants of a product under one reference. You can’t use item_group_id for items that are similar but not variants. When customers check your products, if they are grouped using item_group_id, they will be presented together, and the customer can browse to find the variant they need.

Both product_id and item_group_id are important.

In practical terms, they can help you find your way out of a mix up with duplicate group IDs. Here’s how that works. 

If products in your inventory are made from different materials but have the same color, Google might recognize the entries as duplicate group IDs and remove one of them. For example, you sell brown shoes, and one variation is made of leather while the other is made of canvas, but you haven’t specified the product material. 

This will result in having two group IDs for brown shoes. To resolve it, you’ll have to provide value for the material attribute.

Since each item has a unique product ID, you can use it to sort such issues.

Let’s cover other issues with this attribute.

Common Problems With the item_group_ID Attribute

If you don’t follow Google’s requirements for item_group_id, your items will not be shown to customers. When an item is disapproved, you’ll get a notification in the Diagnostics page.

The most common issue with item_group_id is when advertisers enter wrong values for the attribute.

Here are some suggestions to avoid (or solve) this issue:

  • Each item group should have a unique ID: i.e. one for shirts, other for hats, etc.
  • Use multiple variant attributes along with the item groupID: provide values for as many attributes, including size, color, material, age group, gender, pattern, etc.
  • All items in the item group ID should have values for the same number of attributes: don’t provide color, size, and material for one item, but only size for another item within the same item group.
  • Use parent SKU for all items in an item group: the item group ID remains the same, while variations are expressed by adding additional references (remember, dashes and underscores are accepted).
  • Don’t group together items that aren’t variants: i.e. group shirts of different color, but not shirts and trousers.
  • Add other product identifiers when possible: add both UPIs (GTIN, MPN, and brand) and item_group_id. This, along with product_id, will make it easier for Google to identify each item.

Make sure to provide rich product data for items in your feed. This is general advice, but it will help you solve issues with item_group_id, as well as issues with other attributes.

Help Google Present Your Offer to Customers With Item_group_ID

Getting your complete offer in front of potential buyers on Google Shopping is tricky if you don’t group product variants under one reference. The item group ID attribute makes it easy for Google to understand if the products you offer are part of a large inventory of different variants.

What works for simple (individual) products might not work for variables (product variants), so use this attribute, along with other inputs of product data, and help Google serve your ads to relevant users.

Dennis Moons

Dennis Moons is the founder and lead instructor at Store Growers.

He's a Google Ads expert with over 12 years of experience in running Google Ads campaigns.

During this time he has managed more than $5 million in ad spend and worked with clients ranging from small businesses to global brands. His goal is to provide advice that allows you to compete effectively in Google Ads.

Follow him on Twitter or LinkedIn.

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