Barcode Validator
Check any barcode number: length, characters and check digit.
What this checker does
Paste a barcode number and get a full breakdown rather than a verdict: which symbology accepts it, the normalised value, the expected and actual length, the check digit you supplied next to the one that was calculated, whether every character is encodable, and — when something is wrong — the corrected number, ready to use with one click.
Automatic detection
Leave the type on "Detect automatically" and every format the tool can validate is tried. Some numbers are legitimately valid as more than one thing: a thirteen-digit number beginning 978 is both a valid EAN-13 and a valid ISBN, and you are told so instead of being given an arbitrary answer. Pick a specific type to check against one standard.
What "valid" actually means
A valid number is well-formed: right length, right characters, right check digit. That is a mathematical statement, not a commercial one. It does not mean the number is registered to you, that it identifies a real product, or that a retailer will accept it. Those come from GS1 and from your trading partners.
Formats covered
UPC-A, UPC-E, EAN-13, EAN-8, ITF-14, ITF, ISBN, ISSN, Code 128, GS1-128, Code 39, Codabar, MSI and Pharmacode. Each carries its own rules — length for the GTIN family, character sets for Code 39 and Codabar, Application Identifier structure for GS1-128, a numeric range for Pharmacode.
From check to barcode
When a number checks out, a preview of the symbol appears right there, with a link straight to the matching generator so you can set the size, colours and text and download it. The whole report can be copied as text for a ticket or an email to a supplier.
Privacy
Every check digit is calculated in your browser. Product numbers, batch codes and GS1 element strings are commercially sensitive, and none of it is sent anywhere or written to storage.
Frequently asked questions
Does a valid check digit mean the barcode is registered?
No. It means the number is mathematically well-formed. Registration of GTINs is a matter for GS1 and your trading partners.
Why is my number valid as two different types?
Some formats overlap — a 978-prefixed EAN-13 is also a valid ISBN. The tool lists every match rather than picking one for you.
It says the check digit is wrong. What do I do?
The correct digit and the corrected full number are shown, with a button to apply it. Confirm against your source data before using it.
Can I check a scanned code?
Yes. Scan it with the barcode scanner, copy the value, and paste it here.
Curious how we build and check these codes? Read our methodology, and the disclaimer on what a generated barcode image is and is not.