How to Set Up DKIM for FastMail?

1 min readBy Team EA

DomainKeys Identified Mail (DKIM) is an anti-tamper protocol that keeps your emails secure in transit. DKIM uses digital signatures to check that the email was sent by a specific domain.

Setting up DKIM on Fastmail is very simple and requires you to follow a few simple steps.

Fastmail uses three different CNAME records to sign your outbound emails with DKIM.

The records are shown below with {mydomain.com} to represent your domain name.

Fastmail table listing DKIM CNAME selectors and values

Login to your DNS management console and publish these three CNAME records correctly and wait for 24-48 hours for the changes to take effect.

After they have been verified, check your DKIM record using our free DKIM validator tool.

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