Review the information below before downloading the suppression list.
This suppression list contains MD5 hashes of normalized email addresses, not the actual email addresses.
An MD5 hash is a one-way representation of an email address. The same normalized email address will always produce the same MD5 hash, allowing you to identify unsubscribed recipients without exposing their actual email addresses.
Each email address is normalized before being hashed:
The original email is normalized and then converted into an MD5 hash.
User@Example.com
user@example.com
b58996c504c5638798eb6b511e6f49af
To determine whether one of your contacts has unsubscribed:
If a match is found, the contact has unsubscribed and should no longer receive email communications from your system.
$hash = md5(strtolower(trim($email)));
If the generated hash exists in the suppression list, the email address is considered unsubscribed.
We provide MD5 hashes to:
MD5 hashes should not be treated as encryption. Although this list does not directly contain email addresses, hashes of common or known email addresses may be matched by someone who already possesses those addresses.
You should only compare these hashes against email addresses that you already possess and are authorized to process.
Before sending a campaign, ensure your mailing list excludes any contacts whose MD5 hashes appear in this suppression list.
By downloading this file, you acknowledge that you are responsible for using the suppression list in compliance with applicable privacy laws and email regulations.