gtin is the number under the product’s barcode: 8, 12, 13 or 14 digits (EAN-8, UPC, EAN-13 or ISBN-13, ITF-14), with a valid check digit, spaces and dashes ignored. Google recommends it for all products with a GTIN assigned by the manufacturer; a product submitted without its GTIN may have limited visibility or could be disapproved, an invalid GTIN disapproves the product, and a product with none should say so with identifier_exists.
| Attribute | gtin |
|---|---|
| Requirement | Recommended for all products with a GTIN assigned by the manufacturer; not needed for products without one. |
| Format |
|
Google’s rules for gtin
- Use the exact number from the barcode; no placeholders, no reuse across variants.
- Convert ISBN-10 to ISBN-13.
- Keep leading zeros: a 12-digit UPC that starts with 0 has twelve digits.
- When in doubt, leave it empty rather than guess.
Common mistakes, and the error each one becomes
- A SKU, a placeholder or a number with a dropped leading zero. → Invalid value [gtin]
- The field empty on branded goods that have barcodes.
- One GTIN copied across sizes or products. → Same GTIN but differing value [brand]
Where the value comes from on a connected store
| Shopify | The variant’s Barcode field, normalised to digits and validated; invalid values are dropped rather than sent. |
|---|---|
| WooCommerce | The GTIN, UPC, EAN, or ISBN field WooCommerce 9.2 added, or the GTIN Google for WooCommerce stores, per variation, falling back to the parent; invalid values are left out. |
The free feed check reads this attribute from any feed file and reports the defects above; every check is listed. For one value at a time: Validate a GTIN’s check digit.
Questions merchants ask
What happens without a GTIN?
If the product has a GTIN assigned and it is not submitted, Google says the product may have limited visibility or could be disapproved, and that accurate matching to products can’t be assured. A product that has no GTIN assigned doesn’t need one. An invalid value disapproves the product.
Can I use brand and MPN instead?
For products that have no GTIN, yes: brand plus mpn is the alternative identifier pair. For products that have a GTIN, Google wants the GTIN.
Where do I find GTINs for resold products?
On the packaging under the barcode, in the supplier’s price list, or on the invoice lines. GS1 is the body that issues them.
Sources
- GTIN [gtin] — Google Merchant Center Help
- How to fix: Invalid value [gtin] — Google Merchant Center Help
- GS1: Global Trade Item Number (GTIN)
- About unique product identifiers — Google Merchant Center Help
- WooCommerce 9.2: Pre-release updates (global_unique_id field)
- WooCommerce: Variable Products documentation