UPC & Barcode Validator

About this tool

The barcode validator checks a column of UPC, EAN, and GTIN codes against the GS1 check-digit standard. Upload a CSV, pick the barcode column, and every row is verified — the tool flags typos, wrong lengths, and stray non-digit characters, then hands back the file annotated with a barcode type and a valid yes/no column.

A single mistyped barcode gets a product rejected by Shopify, Amazon, or Google Merchant Center, and the error messages rarely say which row is wrong. Validating the whole column first surfaces every bad code in one pass. The file is checked in your browser and never uploaded anywhere.

How to use it

1. Upload your CSVAdd the product or inventory file with a column of barcodes.
2. Pick the barcode columnWe auto-select a likely column — confirm or change it, then validate.
3. Download the checked fileEvery row gets a barcode type and a valid yes/no flag so you can fix the bad ones.

Frequently asked questions

Which barcode formats does it check?

UPC-A (12 digits), EAN-13, EAN-8, and GTIN-14. Each is verified with the standard GS1 mod-10 check digit — the same math retailers and marketplaces use.

What does a failed check digit mean?

The last digit of a barcode is a checksum computed from the others. If it doesn't match, the barcode has a typo or a missing/extra digit. The tool flags the exact row so you can correct it.

My barcodes lost their leading zeros in Excel — will they fail?

Yes. Excel drops leading zeros and turns long numbers into scientific notation, which breaks the digit count. Fix the column first — the Excel to CSV converter keeps values as text — then validate here.

Does a valid check digit mean the barcode is real?

No. The check digit only proves the number is well-formed. It cannot confirm the barcode is registered to your product — only that it has no typos and the right length.