Overview

SHA-512 is a variant within the Secure Hash Algorithms family of cryptographic hash functions. It was published as a Federal Information Processing Standard (FIPS) by the National Institute of Standards and Technology (NIST).

OPTIZMO has now added support for the storage and distribution of SHA-512 hashed email addresses in response to widespread adoption of this standard by the technology industry.

Like MD5, the SHA-512 is a one-way encoding, meaning that you cannot recover the original string from the hash. However, the SHA-512 hash algorithm addresses many of the shortfalls of MD5 such as collision resistance and lookup tables. It produces a 128 character hash - four times larger than the hash produced by the MD5 algorithm (32 characters).

When you download an Opt-Out List hashed using SHA-512, you must hash your local recipient email list in SHA-512 prior to comparing it against the Opt-Out List. As MD5 and SHA-512 are vastly different, any comparisons between the two will yield invalid results. 

Example for verifying your SHA-512 algorithm

Input

test@email.com

Output SHA-512 Hash

5490d5e891d1707a0cd058c583cb6adc3a7674298cfb9d9f0c637239db9fe40d8fd2ca22b2608aa48339af109528dcf8866b928662d40f182bf80750c705164f

Output MD5 Hash

93942e96f5acd83e2e047ad8fe03114d