What does it mean to “hash” an email?
Hashing an email involves using an algorithm (such as SHA256, MD5, or SHA1) to convert that email into a unique, unrecognizable jumble of characters in order to identify & target travelers online while still ensuring user privacy. For example, after hashing “john.s@gmail.com”, it would become “d7984b9599199b83cc213f19cb2906d2”. Hashing emails is a 'one-way function', meaning it cannot be reversed back into the original email.
What can hashed email do for us that a third-party cookie can’t?
Until now, marketers have received most information from cookies. There’s just one problem: cookies don’t work across multiple devices. In addition, cookies can be blocked and don’t connect with mobile activity. Emails are quickly becoming the most reliable method of cross-device identification. This means you can take a hashed email address in your database and use this information for people-based marketing - reaching them in all of the spaces they’ve logged in with that email, like their favorite websites, social media platforms, or apps on their mobile devices.
How do you collect hashed emails?
The new Sojern pixel contains a piece of code that will let us automatically hash emails for you and send them back to us when a user logs in and/or completes a booking on your website where an email address is required. In order to ensure data privacy, Sojern does not see or collect the raw email address.
Can I hash the emails myself and send them to Sojern?
Yes. Just make sure you use the SHA256 hash function (which is mandatory). We also encourage our customers to share the SHA1 and MD5 versions of the hashed email, too. The more, the better! Never use online hashing tools, as this requires sharing raw data with a 3rd party.
Does a user have to be logged in to my site in order to hash and capture their email?
If a user does not log in to your website, Sojern will still be able to hash and capture their email when they complete a booking (provided an email address is required to complete that booking). When we've captured their hashed email, we'll associate it with a first-party cookie ID so that the next time a user visits your website, they won't have to log in again in order for us to retarget them.
If a user does not log in or complete a booking on your website, they will not be able to retarget them as they browse around elsewhere online. This is why it is crucial to start building a strategy for collecting emails using a permissions-based approach that also provides value to the user in exchange for sharing their email with you.
Can Sojern determine that multiple emails (e.g. personal and work emails) belong to the same consumer?
Yes.
Are there other companies that are taking the same approach as Sojern?
Yes. Industry giants like YouTube and Facebook have supported hashed email for several years now. DSPs like The Trade Desk and Xandr also use hashed email as an identifier. In addition, the IAB and other industry groups have acknowledged that hashed emails will be a critical consumer ID in the absence of third-party cookies.
If a user is logged-in to their browser, will that email be automatically shared with me/Sojern for advertising purposes?
No, the browser does not provide the email login details to us. Google Chrome, for example, is a separate system from Google’s DV360. Google will not support the use of emails for ad targeting within Chrome when third-party cookies are phased out.
Can I use single sign-on (SSO) solutions (i.e. login with Google, Facebook, Twitter, etc. account) to capture a user's hashed email?
Yes, provided the user's email address is recorded in your website data layer.
Can you capture hashed emails from other actions on my website beyond just logins? e.g. newsletter signups, contact us forms, brochure downloads, etc.
Yes, provided we have a pixel implemented on those pages, or the information is passed to us via other means, e.g. data transfer.
Will Sojern use hashed emails alongside third-party cookies whilst they are still supported in Chrome?
Yes.
Is retargeting via hashed email limited to authenticated environments (e.g. social media channels, apps, websites, CTV accounts, etc.)?
Yes.
