Where does this come from, and can I check it?

Modulo 10 algorithms check barcode scanner accuracy to flag unreadable scans. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Mondo Knows Facts

Barcode numbers end with a mathematically calculated check digit

Modulo 10 algorithms check barcode scanner accuracy to flag unreadable scans

The last number on a twelve-digit UPC barcode is a mathematically calculated check digit. Scanners apply a modulo 10 algorithm to odd and even position digits to verify reading accuracy. If a damaged bar causes misreads, the calculated check digit fails to match and the scanner beeps an error.

Where this comes from

NIST

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Tags: barcodes, maths, retail

Barcode numbers end with a mathematically calculated check digit: the short answers

Where does this come from, and can I check it?: Modulo 10 algorithms check barcode scanner accuracy to flag unreadable scans. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.