An email hash is a 32, 40, or 64-character code code crated via a hashing algorithm. This code represents an email — in other words, it’s a unique identifier, tied to individual email addresses.
- Message-digest or MD5: The MD5 algorithm produces a 32-character hash.
- Secure hash algorithm 1 or SHA-1: Designed by the United States National Security Agency, this code is a federal information processing standard. This algorithm produces a hexadecimal number 40 characters long
- Secure hash algorithm 2 or SHA-2: The SHA-2 algorithm consists of multiple hash functions with values that vary in size, the most common being SHA-256, which produces an email hash of 64 characters
Email hashes are encrypted, irreversible, and anonymous codes. This quality makes an email hash a secure way of identifying individual email addresses while protecting personally identifiable information (PII). Furthermore, different parties can hash an email and arrive at the same value. What does this mean for email advertising? It means that different sides of the industry can work together to target and reach audiences while protecting their privacy.
Why is email hashing important?
As the industry prepares for the cookiepocalypse, the hashed email will play an important role in identifying and targeting audiences. Unlike third-party cookies, hashed emails are stable identifiers which allow publishers and advertisers to track users across channels and devices. So, even well after the demise of the third-party cookie, publishers and advertisers can continue to identify users.
Encrypted email identifiers and the changing identity landscape
We interviewed more than 200 senior marketing and publishing executives to shed light on how they’ll leverage the email address prior to and after the cookiepocalypse. Check out the survey findings to learn more about encrypted email identifiers and their role in the changing identity landscape.
Our CEO, Matt Keiser, also shared his thoughts on email as a critical component to identity in AdExchanger. Check out wha the had to say, here.
