ISO/IEC 7064 is a standard promulgated by the International Standards Organization (ISO) and International Electrotechnical Commission (IEC) that defines algorithms for calculating check digit characters. The checks should be applicable to alphanumeric strings and should be able to detect all single substitution errors, all or nearly all single local transposition errors, all or nearly all circular shift errors, a high proportion of double substitution errors, a high proportion of all other errors.
It is referred to by other ISO standards:
and by other systems: