Bulk GTIN checker for UPC, EAN and ISBN
Paste barcodes from your products or a feed export and see at once which ones Google Shopping is likely to reject: wrong check digits, wrong lengths, letters, GS1 restricted or coupon prefixes, short UPC-E codes and duplicates.
Anonymous: we keep only daily counts of checks. Store addresses and results are not saved, and there are no tracking cookies in the tool.
How it works
01Paste up to 500 codes
One per line, or separated by commas or tabs. Spaces and dashes are ignored.
02We apply the GS1 rules
Check digit (mod 10), length 8, 12, 13 or 14, restricted and coupon prefixes, as in the app’s feed audit.
03Fix what’s flagged
See each problem with the expected check digit, plus duplicates that would make Google merge different products.
Questions about this tool
What is a GTIN check digit?
The last digit of a GTIN, calculated from the other digits with the GS1 mod-10 algorithm. A wrong check digit usually means a typo or a made-up number, and Google rejects the code.
Which prefixes are restricted?
Google doesn’t accept GTINs in the restricted ranges (prefixes 02, 04 or 2) or the coupon ranges (GS1 prefixes 05, 98 or 99). This checker flags 02, 04 and 20–29 (2 for 8-digit codes) as restricted and 05, 981–984 and 99 as coupon prefixes; other codes starting with 98 are not flagged, so check them against Google’s rule.
Why are 8-digit codes starting with 0 flagged?
They are usually UPC-E codes, a zero-suppressed form of a 12-digit UPC-A. Google expects the full 12-digit UPC-A.
Why do duplicates matter?
One GTIN identifies one product. When different products share a GTIN, Google may merge them or reject them. Codes are compared as 14 digits, so 012345678905 and 0012345678905 count as the same.