Google Merchant Center GTIN Requirements: What They Are and How to Fix Errors

If you have ever seen a "missing GTIN" warning in your Merchant Center Diagnostics tab, or had a product disapproved for an invalid GTIN, this guide is the practical reference you need. We cover what GTINs are, exactly when Google requires them, how to find the right number for products you sell, what to do if you manufacture your own products, and how to diagnose and clear every GTIN error type that appears in Diagnostics.

What GTINs are and why Google cares about them

GTIN stands for Global Trade Item Number. It is the umbrella term for the family of barcode identifiers that GS1, the global standards organization, assigns to commercial products. In practice, the GTINs you will encounter most often are:

• EAN-13 (European Article Number): 13-digit code used on most products sold in Europe, Australia, and Asia.
• UPC-A (Universal Product Code): 12-digit code, dominant in the United States and Canada.
• ISBN-13: The 13-digit book identifier, which is a subset of EAN-13 and a valid GTIN.
• ITF-14: 14-digit code used on outer cartons and shipping cases, not usually relevant for individual product listings.

Google uses GTINs to match your product listing to authoritative product data from the manufacturer. When you submit a correct GTIN, Google can pull in verified product information (correct title, accurate description, official images), can rank your listing against other sellers of the same product, and can apply price competitiveness scoring. Without a GTIN, Google treats your product as harder to verify, which results in lower placement in Shopping results even if everything else in your feed is correct.

When Google requires a GTIN and when it does not

The rule is simpler than most guides make it sound:

• Branded products with a GTIN assigned by the manufacturer: always required. If a product was made by a brand (Nike, Sony, Bosch, anything) and has a barcode on the packaging, you must submit the GTIN. No exceptions.
• Unbranded products and custom-made goods: use identifier_exists: false. If the product has no brand, no GTIN, no MPN, and no barcode, set this attribute to false. Google accepts that some products genuinely have no global identifier.
• Products where you manufacture under your own brand: you need to assign a GTIN yourself (see the GS1 section below).

How missing GTINs affect your Shopping performance

It is worth being precise here, because "missing GTIN" shows up in two different ways in Merchant Center, and they have different consequences.

A missing GTIN warning (not an error) means Google is telling you that your product would perform better with a GTIN. The product is still approved and running. Shopping visibility is reduced because Google cannot match your listing to its product knowledge graph, so you are less likely to show up in rich Shopping panels, price comparison results, or Google Lens product searches. You are not suspended; you are just leaving traffic on the table.

A GTIN validation error means you submitted a GTIN but it failed Google's checksum validation. This causes a disapproval for that specific product. The product stops running in Shopping until you either correct the GTIN or remove it and set the appropriate fallback.

How to find the correct GTIN for products you resell

Three reliable sources:

1. The product packaging. Scan the barcode with your phone camera or a barcode scanner app. The number under the barcode is the EAN or UPC.
2. The manufacturer directly. Email or call the manufacturer and ask for the EAN-13 or UPC-A for each SKU you sell. Most manufacturers keep a product data sheet with GTINs for wholesale partners.
3. GS1 Verified by GS1 database. Visit gs1.org/services/verified-by-gs1 and search by GTIN or brand. This is the authoritative source.

For books, the ISBN-13 on the back cover is the GTIN. You can use it directly in the gtin attribute without any conversion.

What to do when you manufacture your own products

If you make your own products under your own brand, you need to assign GTINs yourself. The process:

1. Apply for a GS1 Company Prefix at your national GS1 member organization (GS1 Germany, GS1 Netherlands, GS1 UK, etc.). The prefix is a number block that identifies your company. From that prefix, you can generate GTINs for every product you sell.
2. Cost in Europe: roughly 190 euros per year for a small-company prefix that lets you assign up to 10 GTINs, scaling up based on the number of products. In the US, GS1 US pricing starts at $250 for up to 10 products.
3. Time: applications are processed within a few business days in most countries.
4. After approval: use the GS1 tools to generate valid GTINs for each product, print barcodes, and submit those GTINs in your Merchant Center feed.

If you are not ready to apply for a GS1 prefix, set identifier_exists: false on your own-brand products. This is acceptable for unbranded or custom products, but it will limit your Shopping visibility until you have real GTINs assigned.

The brand attribute and why it matters alongside GTIN

Google uses the combination of gtin, brand, and mpn (Manufacturer Part Number) to identify products. If you submit a GTIN but leave the brand attribute blank or fill it with a generic placeholder like "N/A", Google may still struggle to match your listing. Always submit the correct brand name alongside the GTIN. For your own-brand products, use your actual company name as the brand.

There is no "brand exception" field in the standard feed spec. When merchants refer to a "brand exception", they usually mean the correct use of identifier_exists: false for unbranded goods, combined with leaving the brand field empty or set to a descriptive label like "Unbranded". Do not invent a fictional brand name to work around GTIN requirements.

How to find and fix GTIN errors in Diagnostics

In your Merchant Center account, go to Products > Diagnostics. Filter by "Invalid GTIN" or "Missing GTIN". The issue list will show you which products are affected and the specific error code.

After fixing errors in your feed, re-upload or trigger a feed refresh. Google typically re-processes updated products within 24 hours, though large feeds can take up to 72 hours to fully re-index.