GS1 Mod-10 utility

GTIN-12 / UPC-A check digit calculator

Enter 11 body digits to generate a 12-digit GTIN-12 / UPC-A, or switch to Validate and enter all 12 digits. Leading zeros are preserved.

Calculator

GS1 Mod-10 check digit

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Enter exactly 11 ASCII digits.

A matching check digit detects some entry errors. It does not prove that an identifier was issued, assigned correctly, authentic, or linked to a particular product or location.

Supported formats

Exact lengths, one shared rule

GTIN, GLN and SSCC use the same GS1 Mod-10 arithmetic but have different required lengths. CheckDigit validates the length before calculating.