Product labels
A mathematically valid UPC is not a licensed one
A UPC can be arithmetically valid and still not be a code you are allowed to put on a product. Validity means the check digit matches the other digits. Assignment is the separate question of who the prefix belongs to and which product it identifies.
The label generator’s notice is the short version: use a UPC assigned to your product. The tool creates labels. It does not issue or register product identifiers.
| Question | What answers it |
|---|---|
| Does the check digit match? | The 11-digit calculation, or a 12-digit validation |
| Who may use the prefix? | The GS1 assignment for that prefix |
| Will the printed bars scan? | Size, contrast, quiet zone, and a scan of the print |
What to do with a code you were given
Enter the digits you were given, including any leading zero. Complete the check digit only when you were given 11 digits and the twelfth is the check. If all 12 were supplied, a mismatch means the code was copied wrong or altered. It is not a prompt to invent a replacement.
Copying a label for another unit of the same product is ordinary. Putting that same code on a different product needs the issuer’s identification rules, not a new random number that happens to pass the check.
Print quality is a third question
The retail preset uses an X-dimension of 0.330 mm, a quiet zone of at least 2.97 mm at that size, and a main bar height of 22.85 mm. Those figures come from the sizing guidance used for the preset. They do not certify a particular printer, sheet, or PDF until someone measures and scans the output.
Sources and tools
Related guides
Common questions
If the check digit passes, is the code mine?
No. The check digit is a math test. Licensing and product assignment come from the identifier issuer.
Can the tool look up who owns a prefix?
No. This tool does not call a product database or a GS1 account.