How-to (complements invalid_gtin / missing_gtin) · Disapproval when the value fails format or check-digit

Invalid GTIN: internal SKU or shop barcode in the gtin field

Google received a gtin that is not a manufacturer GTIN. On a small Shopify shop that is usually the SKU pasted into Barcode. On Shopware it is often the product number or manufacturer number sitting in the EAN field. Valid GTINs are 8, 12, 13, or 14 digits, numerals only, and they must pass the GS1 check digit. An internal SKU almost never does.

Common causes

• ·Shopify: the variant SKU was pasted into Barcode. Google & YouTube maps Barcode → gtin.
• ·Shopware: the internal product number or manufacturer number was entered in the EAN field the Shopping feed exports as gtin.
• ·Letters, dashes, or spaces that are part of a house SKU (TEE-BLU-M, SKU 1042)
• ·Wrong length (6-digit shop codes, 10-digit internal IDs)
• ·A made-up number invented to clear a missing-GTIN warning
• ·The same shop code reused on every size/color. Each variant that has a real GTIN has its own.

How to fix it

1. 01
   Take the GTIN from the product packaging or the manufacturer. Do not invent one. Do not reuse a similar product's code.
2. 02
   Shopify: put the manufacturer UPC/EAN/ISBN in the variant Barcode field. Leave SKU as your internal code. Save and let Google & YouTube re-sync.
3. 03
   Shopware: put the manufacturer EAN/UPC in the EAN field. Keep the shop product number and manufacturer number out of gtin. Confirm the Shopping feed / product-comparison template exports EAN as gtin, not the product number.
4. 04
   If the value is questionable, check the digit count (8, 12, 13, or 14) and run it through a GS1 check-digit calculator. Restricted GS1 prefixes (02, 04, 2) and coupon ranges are not valid GTINs for this field.
5. 05
   If the product truly has no barcode (custom, handmade, vintage without one), leave gtin empty and set identifier_exists to false / no — only then. Do not set that flag as a default on branded goods that have a barcode. Google's identifier-exists article says a false value, when Google can see a UPI exists, is a warning.
6. 06
   Re-upload or wait for sync. Format issues can take 24–72 hours to leave Needs attention.

Checked against Google's documentation: How to fix: Invalid GTIN in unsupported format · GTIN [gtin] · Identifier exists [identifier_exists] · About unique product identifiers