Bulk Barcode Validator
Paste up to 1,000 GTIN / UPC / EAN codes (one per line) and validate every check digit at once. Runs in your browser — your data never leaves your device.
What gets checked
Each line is cleaned (spaces and dashes removed) and validated against the GS1 Mod-10 formula. Accepted lengths: 8 (GTIN-8), 12 (UPC-A), 13 (EAN-13/ISBN-13), 14 (GTIN-14). Invalid rows show the expected check digit so you can fix them instantly.
Common sources of invalid barcodes
Excel stripping leading zeros is the most common cause of "invalid" UPCs: 036000291452 becomes 36000291452 (11 digits). Re-format the column as text and restore the zero. Other frequent causes: an extra digit pasted from a supplier sheet, O (letter) typed instead of 0 (zero), and codes truncated during CSV export.
FAQ
Can I validate ISBNs with this tool?
ISBN-13s yes — they are EAN-13 barcodes, so paste them like any other code. ISBN-10s no: they use a different checksum and may end with an X. Convert them first with the ISBN converter.
Is my list uploaded anywhere?
No. Validation runs entirely in your browser with JavaScript — the codes never leave your device, which also makes the tool safe for unreleased product lists.
What do I do with the invalid rows?
Each invalid row shows the expected check digit, so you can fix typos directly in your spreadsheet. If a whole column is off by one digit, check for Excel stripping leading zeros — format the column as text and re-paste.
More than 1,000 codes, or need this in your own system?
Our pay-per-use validation & classification API validates up to 100 barcodes per call — first 25 calls per month free.
Validation uses the official GS1 Mod-10 formula. GS1 prefix ownership is not verified.