Check Digit Calculator

5-step algorithm for check digit calculation:
Let’s assume that we are using the fictitious code 05432122345.

  1. Add all of the digits in the odd positions (digits in position 1, 3, 5, 7, 9, and 11)
    0 + 4 + 2 + 2 + 3 + 5 = 16
  2. Multiply by 3.
    16 * 3 = 48
  3. Add all of the digits in even positions (digits in position 2, 4, 6, 8 and 10).
    5 + 3 + 1 + 2 + 4 = 15
  4. Sum the results of steps 3 and 2.
    48 + 15 = 63
  5. Determine what number needs to be added to the result of step 4 in order to create a multiple of 10.
    63 + 7 = 70

The check digit therefore equals 7.

UPC/EAN bar code check digit calculator:

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