This sounds simple enough, but since the length of the hashed string will be considerably longer than the original string, validations on this field (ssn must be nine digits) will fail. I've considered placing the hashed value into a hidden field, but then the unencrypted value will be posted and the hashing accomplishes nothing. If I clear out the original value I lose server-side validations. Anyone have any ideas of the best way to accomplish this? Notice: This communication, including any attachments, is intended solely for the use of the individual or entity to which it is addressed. This communication may contain information that is protected from disclosure under State and/or Federal law. Please notify the sender immediately if you have received this communication in error and delete this email from your system. If you are not the intended recipient, you are requested not to disclose, copy, distribute or take any action in reliance on the contents of this information.