Configuring check digit validation

  • 28/10/2025
  • 3 minutes to read

Check digit validation adds an extra layer of control when processing payment references in Continia Banking. It ensures that references are not only correctly formatted but also mathematically valid according to industry standards.

A check digit is a single number calculated from the other digits in a reference. It helps detect errors caused by incorrect data entry or transmission. Many national and international payment formats use check digits to improve data integrity.

Continia Banking supports the following check digit algorithms:

  • Modulus 10 (Luhn algorithm) - commonly used for credit cards and some payment references.
  • Modulus 10 recursive - a variant of Modulus 10 used in certain Scandinavian payment systems.
  • Modulus 11 - commonly used for Norwegian KID numbers and other payment reference formats.

To configure a payment reference rule that uses check digit:

  1. On the Payment Reference Rules page, on the action bar, click New to create a new payment reference rule.
  2. In the rule setup, go to the Validation FastTab and enable the Check Digit option.
  3. When you enable Check Digit, the following fields become mandatory (indicated with a red asterisk):
    • Check Digit Algorithm - choose the algorithm to use (for example, Modulus 10).
    • Check Digit Position - specify the position of the check digit in the reference (for example, 10 for the 10th character).
    • Check Digit Calculation Start Position - define where to start the calculation (for example, 1 to start from the first character).
    • Check Digit Calculation Length - set how many characters to include in the calculation (for example, 9 to use the first nine characters for calculation.
  4. Save the rule.
  5. Use the Test function to verify that check digit validation works as expected.