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Returns an MD5 hash.

 string md5( string input )

Returns an MD5 hash of a string, as a 32-character string representation of hexadecimal.


 {md5('test')} = 098f6bcd4621d373cade4e832627b4f6

MD5-hash a User’s Email Address

Use Case: Pass an anonymized user identifier such as the MD5-hash of their email address in a URL as a query string parameter.



Explanation: Sending the hash of an email address allows you to compare this against your internal record of user hashes and identify the user. (Note that as a security and deliverability best practice, we recommend never directly passing the user’s email address in a URL.) You can use this technique in the Auto-Append Link Parameters section of the Template and Campaign Editors, for example.