Out of all the product identifiers used for Google Shopping, GTIN is king. It’s arguably the most talked about identifier around and has been known to cause many headaches for online retailers over the past few years as Google began tightening GTIN requirements.
Regardless, it is a necessary evil that online retailers must tackle if they want to see results from their shopping ads.
We’ve rounded up important GTIN information to give you the low-down on the ever-so-talked about attribute and why it should matter to you and your listings.

GTIN, short for Global Trade Identification Number, uniquely identifies trade items, products or services.
There are various types of ID numbers that fall under GTIN. These include:
UPC (Universal Product Code)
EAN (European Article Number)
JAN (Japanese Article Number)
ISBN (International Standard Book Number)
ITF-14
Check out more details on each of these ID numbers here.
Google now requires GTINs for all new products where a GTIN is assigned by the manufacturer.
If you’re product requires a GTIN, you must also submit the brand attribute. MPN is recommended but not mandatory.
The GTINs submitted to Google must follow the guidelines defined in the official GS1 validation guide.
Products that come in multiple variations such as color or size should have their own GTIN value assigned to them. For example, if you are selling a shirt that comes in red and blue, both shirts should have a unique GTIN.
GTINs are usually found on the barcode on the product packaging or book cover. If you can’t locate the product GTIN, you should reach out to your product manufacturer. For more assistance on where to find the GTIN, refer to Google’s help article.
There’s a reason why GTINs are such a talked about attribute-- they actually help improve your ads.
The more relevant information that you add to your product ads, the more likely you are to appear in relevant searches. GTINs help Google to better classify your products in their catalog and get them in front of the right shoppers. This leaves more potential for conversions.
While the process of locating your product’s GTINs may seem like a headache at first, it can pay off in places outside the world of Google Shopping. This includes helping you list more effectively on marketplace giants such as Amazon, eBay and Walmart.

Not all products may have a GTIN assigned to them. According to Google, these may include:
If your product does not have a GTIN assigned, you’ll want to submit both the brand and mpn attributes instead.
On the flip side, if you don’t submit a GTIN for a product that requires one, expect to receive errors in your Merchant Center account. Be sure to carefully read over Google’s GTIN requirements before submitting without the attribute.
GTINs play a key role not only in Google Shopping feed optimization, but in the world of online retailing. While it may seem like a pain to round up all of your GTINs now, your listings will thank you later.
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