A method for enhanced validation of cryptograms for varying account number lengths includes: storing one or more primary account numbers and a plurality of formatting templates, each template being associated with an account number length; receiving a selection indicating a specific primary account number; identifying a specific formatting template where the associated account number length corresponds to a length of the specific primary account number; receiving an unpredictable number from a point of sale device; generating a cryptogram based on at least the unpredictable number and one or more algorithms; generating a data string, wherein the data string includes at least the generated cryptogram, the specific primary account number, and the unpredictable number, and wherein the data string is formatted based on the identified specific formatting template; and electronically transmitting the generated data string to the point of sale device.