What Is GTIN in Google Merchant Center?

What Is GTIN?

GTIN (Global Trade Item Number) is a standardized product identifier used in global commerce. It is the number encoded in a product's barcode and uniquely identifies a specific product from a specific manufacturer. Common GTIN formats include UPC (12 digits, used in North America), EAN (13 digits, used internationally), JAN (8 or 13 digits, used in Japan), and ISBN (13 digits, used for books).

In Google Merchant Center, the gtin attribute links your product listing to Google's extensive product catalog. When Google can match your product to a known GTIN, it verifies the product exists, enriches your listing with additional data, and improves how your product appears in Shopping results.

Why It Matters for Google Merchant Center

GTINs are one of the most impactful attributes in your product feed. Products with valid GTINs receive measurable advantages in Google Shopping:

Higher ad quality. Google uses GTINs to pull verified product information from its catalog, including manufacturer details, product specifications, and category data. This enrichment improves your listing quality and can increase click-through rates.

Better matching. GTINs help Google understand exactly which product you are selling. Without a GTIN, Google relies on your title and description to identify the product — which is less reliable and can lead to misclassification.

Competitive benchmarking. Google uses GTINs to group identical products across merchants, enabling price comparisons and competitive positioning in Shopping results. Products with GTINs are more likely to appear in product comparison features.

Feed error prevention. Missing GTINs are one of the most common feed errors. While not always required, omitting a GTIN when one exists for your product triggers a warning that can affect your overall feed health score.

For a deeper dive into resolving GTIN-related feed errors, see our missing GTIN fix guide.

How GTIN Works

Where to Find Your GTIN

The GTIN is typically found:

• On the product packaging — The number below the barcode
• On the manufacturer's website — In product specifications or downloads
• From your supplier — Ask for GTINs when ordering inventory
• In the GS1 database — The organization that manages GTIN assignments (gepir.gs1.org)
• On the product itself — Some products have the barcode printed directly on the item

GTIN Formats by Region

All formats are accepted in the gtin attribute. Google normalizes them internally.

Adding GTINs to Your Feed

In your product feed, the GTIN goes in the gtin attribute:

<g:gtin>012345678905</g:gtin>

For Shopify stores, GTINs are entered in the product variant's "Barcode" field. The Google & YouTube app automatically maps this to the gtin attribute in your feed.

Common Issues and Fixes

• "Missing GTIN" warning in Merchant Center — This appears when Google believes a GTIN exists for your product but you have not provided it. Either find and add the correct GTIN, or if the product genuinely has no GTIN (custom, handmade, or vintage items), set identifier_exists to no in your feed.

• Invalid GTIN error — The number you entered does not pass GTIN validation (check digit is wrong). Verify the number against the product barcode. Common causes: entering an internal SKU instead of a GTIN, transposing digits, or using a manufacturer part number (MPN) in the GTIN field.

• GTIN does not match product — Google cross-references your GTIN against its catalog. If the GTIN belongs to a different product than what your listing describes, Google flags it. This can happen when resellers reuse GTIN fields across different products. Ensure each variant has the correct GTIN.

• Products without GTINs — Handmade items, custom products, vintage goods, and some white-label products genuinely have no GTIN. Set identifier_exists: no and provide brand and mpn (manufacturer part number) instead. Do not fabricate GTINs.

• Dropshipped products missing GTINs — If your supplier does not provide GTINs, ask for them directly. Most branded products have GTINs assigned. If the product is unbranded or custom-manufactured, set identifier_exists: no. See our product feed optimization guide for more on handling dropshipped product data.

Related Terms

• Product Feed — The data file where GTINs and other product attributes are submitted to Google
• Product Data Specification — Google's full list of required and optional feed attributes including GTIN
• Supplemental Feed — A secondary feed that can add GTINs to products without modifying your primary feed

Scan your store now to check for missing GTINs and other feed issues that affect your Shopping performance.