Calculate Damm Check Digit
Enter a number into the box and the check digit will be appended below. Note non-digits will be ignored but left in place.
Enter Number To Calculate
Verify Damm Check Digit
Enter a number to test the last digit as a Damm check digit. Text below the box will display if the number is valid or invalid. Note non-digits will be ignored but left in place.
Enter Number To Verify
3 replies on “Damm Algorithm Check Digit Tool”
Nice tool! Would be helpful if it would automatically strip out invalid characters (like hyphens) before calculating the check digit.
Good idea, I will add it to my to-do list. Do you think all invalid characters should be removed and then remaining numbers behave as one large number or something else such as discarding all characters after an invalid one? I think the first way makes most sense.
I have implemented a change that just ignores the invalid characters but leaves them in place. Let me know if you find any bugs