CheckDigit
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GS1 Mod-10 utility

Calculate a GS1 check digit

Choose GTIN, GLN or SSCC, enter the body digits and generate the exact final digit with every weighted step visible.

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GS1 Mod-10 check digit

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Enter exactly 12 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.