What is a hashed email?
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Hashed Email

What is a hashed email?

A hashed email is a privacy-safe representation of an email address created using a cryptographic hash function. This function scrambles the original email address into a unique string of letters and numbers, making it unreadable in its original form. It's like taking a fingerprint of the email address –  it uniquely identifies the email but doesn't reveal the actual address itself.

How do hashed emails work?

When creating a hashed email, the original email address is fed into a hashing algorithm. Common hashing algorithms include MD5 and SHA-256, each generating a different length and format for the hash code. Next, the complex mathematical formula transforms the email address into a fixed-length alphanumeric code. Most importantly, this process is one-way; you cannot reverse the hash to retrieve the original email address.

Why are hashed emails important to marketers?

Hashed emails offer several benefits to marketers including:

  • Privacy Compliance: With increasing data privacy regulations, hashed emails are anonymized and help marketers comply with laws like GDPR and CCP. 
  • Improved Targeting: Marketers can leverage hashed emails to create audience segments based on demographics or past purchases. This allows for targeted advertising campaigns that are relevant and impactful without relying on access to the original email addresses.
  • Cross-Channel Measurement: Hashed emails can be used to track customer journeys across different platforms. By matching hashed emails across devices or websites, marketers gain a more holistic view of campaign performance.

Who needs to know what hashed emails are:

  • Marketers: Anyone involved in email marketing or campaign measurement should understand how hashed emails protect user privacy while still enabling effective targeting and analysis.
  • Data Analysts: Analysts working with customer data need to be aware of data anonymization techniques to ensure compliance with privacy regulations.
  • Privacy Professionals: Those working in data privacy understand the role of hashed emails in protecting user data and ensuring responsible data usage.

Use hashed emails in a sentence:

“Marketers can upload a list of hashed emails corresponding to their existing customer base to drive targeted social media campaigns without compromising user privacy.”