Data Snapshot: MD5 and SHA1 Email Identification and Use Cases

What is MD5 and SHA1?
MD5 and SHA1 are algorithms used to verify data integrity. Originally created for online security applications to verify data integrity, the MD5 (Message Digest 5) and SHA1 (Secure Hash Algorithm 1) hashes are becoming more widely used in marketing applications for transferring data without exchanging personal information. The purpose of these algorithms is to provide data as an input, and generate a fixed size “hash value” as an output. The input data can be of any size or length, but the output “hash value” is always fixed.

In the case of MD5 and SHA1 hashing, the algorithm converts an email address into a character string. Every time a unique email address is run through the MD5 or SHA1 conversion, it produces the exact same result. Hashing through MD5 and SHA1 is a one-way conversion. After conversion, hashes cannot be converted back to email addresses. Using this approach, parties share no actual email addresses, and since the hashes can’t be converted back to actual email addresses, the hashes are useless for any purpose other than matching.

Through advanced digital file compilation and matching, MD5 and SHA1 hashed information can be decoded to provide useful information. Anonymous hashed data can be matched to a database of known hashed information to provide consumer contact information, insights and demographic information.

In instances where a company is using hashes only to target specific sub-segments of consumers, (and do not want to acquire personal consumer information) hashes can be matched, demographics and lifestyle information returned, and online ads instantly targeted based on matched information. This can occur in real-time, with no actual email addresses or consumer contact information being exchanged.
MD5 Conversion Example:
johnsmith@email.com —> MD5 Algorithm —> 9B374134FD3322D5D7370B26D95B4B6D

IP Address Matching Use Case 1: MD5 Hash Decode for Retail Marketing Acquisition
Situation: A large national retailer has an inventory of several million client email addresses that have accumulated due to several acquisitions. The Retailer wants to be able to send offers to these clients of companies they have acquired. The email addresses are in MD5 Hash format. The Retailer wants the email addresses verified and a permission pass sent to the clients.

Solution: Infutor receives the MD5 hashed email addresses and matches them to the Infutor email database. These email addresses are then verified through the Infutor validation process. After Validation is complete, a permission pass is executed to valid email addresses.

Results: The retailer has nearly 3MM new valid and permissioned email addresses to deploy offers from the new company. The average validation rate of reverse hashed data exceeded 85%.
IP Address Matching Use Case 2: MD5 and SHA1 Hash Matching for Web Publishing
Situation: A large, publicly-owned company with a significant presence in EU is looking for U.S. partners who are able to receive a hashed email in real time and return an email address. This company works with Web Publishers to send email communications to website visitors. The EU company is able to extract a hashed email from the website visit and needs a partner who is able to decode the hash with an actual email address for deployment. The Company required sub-500 millisecond response for the hash decode.

Solution: Infutor created a table relating all of our email addresses to both MD5 and SHA1 encrypted algorithms. The reverse hash transactions were made available in real time, within the company specifications.

Results: Infutor is able to process and return up to 1,000 hashed email addresses, submitted simultaneously, in less than 2 seconds, enabling the web publisher meet their ad serving requirements and goals.