DKIM Signing: Why It Matters for Email Security

DKIM (DomainKeys Identified Mail) is an email authentication method that uses cryptographic signatures to verify that an email was actually sent by the domain it claims to come from.

How DKIM Works

DKIM works by adding a digital signature to the header of an email message. The receiving server can verify this signature using the public key published in the sender's DNS records.

DKIM Process

1. **Sending Server**: Signs the email with a private key 2. **DNS**: Public key is published in DNS 3. **Receiving Server**: Verifies signature using public key 4. **Result**: Pass or fail authentication

DKIM Selectors

DKIM uses selectors to allow multiple keys per domain. A selector is specified in the DKIM signature and DNS record:

``` selector._domainkey.yourdomain.com ```

Benefits of DKIM

• **Authentication**: Proves email came from your domain
• **Integrity**: Ensures message wasn't modified in transit
• **Reputation**: Helps build sender reputation
• **Deliverability**: Improves inbox placement

Setting Up DKIM

1. Generate a public/private key pair 2. Publish public key in DNS 3. Configure mail server to sign with private key 4. Test with DKIM validators

DKIM and DMARC

DKIM is one of the authentication methods checked by DMARC. For DMARC to pass, either SPF or DKIM must align with the From domain.

Use our DKIM Generator to create your DKIM records easily!