DomainKeys Identified Mail (DKIM) is a method for email senders to digitally sign email messages in a way that can be verified by email receivers. This allows receivers to verify that the message truly came from the sender, and has not been tampered with. DKIM is intended to address some of the flaws in the existing email system, such as spoofing, phishing, and message tampering.

Steps to Configure DKIM for Proton Mail

• Sign in to your ProtonMail account
• Go to the DKIM tab under Settings > Organization > Custom domains > Actions > Review.
• The 3 CNAME entries that you need to add to your domain’s DNS settings should now be visible.
• ProtonMail will take care of the rest once you have added these records. They will create a brand-new 2048-bit key that is rotated every six months and used to sign your emails.

How to Get Your DKIM Public Key Available for Proton Mail

1. Sign in as the administrator to your DNS provider’s administration console.
2. Go to the DNS records section of each of your domains.
3. Depending on the type of DKIM record that has been provided to you, generate a TXT or CNAME record.
4. Copy and paste the hostname and value
5. Save your record’s modifications and wait 48–72 hours for your DNS to take effect.

Use our free DKIM record lookup tool to validate the published DKIM record.

You can use Skysnag’s free DKIM Checker to check the health of your DKIM record here

Enable DMARC for your domains to protect against spoofing. Sign up for a free trial today!

For more information on Proton Mail DKIM setup, you can refer to their reference documentation