EAN-13, EAN-8, UPC-A and GTIN-14 are all the same GS1 numbering system at different lengths, protected by the same weighted check-digit algorithm. This generates batches of valid-checksum codes in any of the four formats - with an optional prefix, like a real GS1 company prefix - and validates the check digit on any code you already have.

When you'd use this

Seeding a test catalog or staging database with realistic product codes without needing (or being able to get) real, registered GS1 numbers for products that don't exist yet.

Spot-checking a barcode from a spreadsheet or supplier feed - paste it into the validator to confirm the check digit is correct before it goes anywhere near a real label print run.

Common errors

A checksum mismatch on validation means the last digit doesn't match what GS1's algorithm computes from the digits before it - check for a mistyped or transposed digit first.

An "unrecognized length" means the code isn't 8, 12, 13, or 14 digits - those are the only four standard GS1 lengths this format family uses.

Frequently asked questions