What Is a DKIM record?
DKIM (DomainKeys Identified Mail) is an Email Security Solutions standard that ensures that messages are not tampered with while in transit between the sending and receiving servers. As an email leaves a sending server, it employs public-key cryptography to sign it with a private key. Recipient servers then use a public key issued to a domain's DNS to authenticate the message's origin and verify that the message's body hasn't changed during transit. When the receiving server verifies the signature using the public key, the message passes DKIM and is declared valid.
Importance of a DKIM Record
While DKIM isn't necessary, emails signed with DKIM seem more authentic to receiving mail servers and are less likely to end up in the junk or spam folders. Spoofed email from trustworthy domains is a common strategy for dangerous spam and phishing operations, and DKIM makes spoofing more difficult.
DKIM is interoperable with existing email infrastructure and, in conjunction with SPF and DMARC, creates additional levels of protection for domains that send emails. Mail servers that do not support DKIM signatures can nevertheless accept signed messages without issue. It is a security mechanism that is optional, and DKIM is not a globally accepted standard.
We recommend that you add a DKIM record to your DNS wherever feasible to authenticate mail from your domain, even if it is not necessary. Postmark uses it to sign communications, while ISPs such as Yahoo, AOL, and Gmail use it to check incoming mails. We conducted tests that showed that when these security standards are used, communications are more likely to be delivered.
Another advantage of DKIM is that it allows ISPs to create a reputation for your domain over time. When you send an email and enhance your delivery practices (low spam and bounces, high engagement), you assist your domain to establish a positive sending reputation with ISPs, which increases deliverability.
While it is critical to understand what DKIM accomplishes, it is equally critical to understand what it does not solve. DKIM ensures that your message has not been tampered with, but it does not encrypt the contents of your message. Many ESPs employ opportunistic TLS to encrypt messages as they travel between sender and receiver. However, unencrypted messages can still be sent if an email server denies a TLS connection. Once a message is sent, the DKIM signature remains in the email headers but does not encrypt the message's content in any manner.
Importance of a DKIM Record checker
Once you've configured DKIM for an email service, send a message to a managed email address and inspect the Dkim Signature Checker and Authentication-Results headers to check DKIM was successful.
There’s another way to check your DKIM records and perhaps the more feasible one: A DKIM Record checker. The checker ensures that your DKIM records are properly set up and are error-free. It suggests changes if there are errors and ensures a properly authenticated email system. Get your DKIM records checked using EmailAuth’s free DKIM record checker.
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