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EAN-13 Check Digit

Compute EAN-13 check digits and validate barcodes online. GS1 Modulo-10 with instant feedback.

EAN-13 check digit

GS1 Modulo-10: odd positions ×1, even ×3 (from the left, first 12 digits).

Result

8999999123451

How to use

  1. Type 12 digits to compute the check digit, or 13 to validate.
  2. Read instant valid/invalid feedback.
  3. Copy the full code.

FAQ

12 or 13 digits?

12 computes the 13th; 13 validates the whole code.

Does valid mean registered?

No — checksum only. Registration lives with GS1.

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