How to fix “Missing or incorrect barcode (GTIN)” on WooCommerce

Why it happens on WooCommerce

• The GTIN field in the product’s Inventory tab is empty.
• The barcode was saved in an older plugin’s own field, which your Google connection no longer reads.
• The value is an SKU or internal code rather than a real GTIN, so it fails Google’s check-digit test.
• Each variation needs its own barcode, but only the parent product has one.

How to fix it

1. Find the real barcode on the packaging or in your supplier’s product list. Never make one up.
2. Open the product, go to the Inventory tab and enter it in the GTIN field. For variable products, enter each variation’s own barcode.
3. If you stored barcodes in another plugin before, use Google for WooCommerce’s option to move them into the built-in field.
4. If your products genuinely have no barcode (your own brand or handmade), leave the field empty and tell Google the product has no identifier, with your brand filled in.
5. With many products, upload your supplier’s spreadsheet to Merchant Guard: it matches barcodes to products, checks every check digit and sends the valid ones to Google in one go.

Sources: Google: Use the GTIN [gtin]; WooCommerce: Google for WooCommerce and the GTIN field. Platforms and Google change their settings from time to time, so check the issue’s own “Learn more” link in Merchant Center too. For Google’s general rules, see Missing or incorrect barcode (GTIN).