Quick summary
- What it is: DKIM (DomainKeys Identified Mail) is an email authentication mechanism that adds a digital signature to each outgoing message.
- What it's for: it helps configure, send, receive and protect email for a domain.
- When to check it: when creating email accounts, configuring an email client or investigating sending and receiving issues.
DKIM (DomainKeys Identified Mail) is an email authentication mechanism that adds a digital signature to each outgoing message. This signature allows the receiving server to verify that the email has not been modified during transit and that it comes from a legitimate server for the domain.
How does DKIM work?
The DKIM process works in two parts:
- Signing when sending: The outgoing mail server automatically adds an encrypted signature in the header of each email. This signature is generated with a private key known only to the server.
- Verification when receiving: The destination server queries the DNS of the sending domain to obtain the corresponding public key and verifies that the message signature is valid.
If the signature does not match or has been tampered with, the receiving server can treat the email as suspicious or reject it.
Where is DKIM configured?
DKIM is configured as a TXT record in the domain's DNS zone. It usually has a format similar to:
mail._domainkey.yourdomain.com TXT "v=DKIM1; k=rsa; p=MIGfMA0GCS..."
At Bacan, DKIM is usually activated from the control panel (DirectAdmin or cPanel) in the email configuration section.
Why is it important for hosting users?
Without DKIM configured, your emails are more likely to end up in spam or be rejected by strict mail servers such as Gmail or Microsoft 365. Together with SPF and DMARC, DKIM forms the email authentication trio that any domain sending emails should have configured.
When will you encounter it?
You will normally encounter it when diagnosing email delivery problems, when using tools like mail-tester.com or when configuring email for a new domain. If you receive a low score on email tests or your messages end up in spam, reviewing DKIM is one of the first steps.
Why it matters in hosting
Understanding this concept will help you make better decisions when managing your service. In practice, it relates to configuring, delivering, receiving and protecting email for a domain. If it appears in a guide, the control panel or a support response, review the context before making changes.
Related articles
- Webmail
- IMAP
- POP3
- SMTP
- SPF