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Paste a barcode number to check whether its check digit is valid — required before submitting products to Google Merchant Center. Supports GTIN-8, UPC-A (12), GTIN-13/EAN-13, and GTIN-14.
A GTIN (Global Trade Item Number) is the number behind a product barcode. It comes in several lengths: GTIN-8 for small packages, UPC-A (12 digits) mainly in North America, EAN-13 (13 digits) in most other countries, and GTIN-14 for cases and cartons.
The last digit is a check digit calculated from the others. It lets scanners and systems detect typing mistakes. Google Merchant Center and most marketplaces validate GTINs, and an invalid number can cause warnings or disapprovals.
A valid check digit only proves the number is well-formed. Whether it is registered to your brand is a separate question answered by GS1, the organisation that issues barcode numbers.
Barcode numbers (GTINs) identify products across retailers. Marketplaces and Google Merchant Center verify the check digit, so a single typo makes a product invalid — and invalid GTINs are a common reason for disapprovals.
Valid numbers have a correct check digit for their length. Invalid numbers usually contain a typo, a missing leading zero or a digit swapped during copying — compare them with the barcode on the product.
For products without any GTIN, such as handmade items, leave the field empty and use the identifier_exists attribute instead of inventing a number.
A toy distributor in Mexico copied 600 barcodes from supplier spreadsheets into its product feed and received GTIN warnings in Merchant Center.
Pasting the numbers into the GTIN Validator showed 23 invalid check digits. Most were missing a leading zero dropped by the spreadsheet, and a few had two digits swapped. The team corrected them against the product packaging, formatted the column as text to keep leading zeros, and the warnings cleared after the next feed update.
The last digit of a barcode, calculated from the others. It lets systems catch most typing mistakes instantly.
Both are GTINs. A 12-digit UPC-A becomes a valid 13-digit EAN when you add a leading zero.
No. It validates the number's structure. Registration is checked against GS1's database.
Leave the GTIN empty and set identifier_exists to no for that product, instead of inventing a number.
Spreadsheets treat them as numbers. Format the column as text before pasting barcodes.
Yes. GTIN / EAN / UPC Validator runs entirely in your browser — nothing you type or paste is sent to or stored by SeoSpidie.
Yes. The GTIN / EAN / UPC Validator is free to use with no sign-up. SeoSpidie is supported by advertising.
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