DKIM: meaning and how it works
DKIM: the meaning
DKIM stands for DomainKeys Identified Mail. Your mail server signs every outgoing message with an encrypted signature; the corresponding public key is stored in your DNS. The recipient compares the two and can tell whether the message is genuine.
Explanation
Where SPF checks which server is allowed to send, DKIM proves that the content wasn't changed along the way and really belongs to your domain. Together with SPF and DMARC you reduce the chance that your mail is seen as spam or that someone misuses your name. If you want to set it up, read DKIM explained.
Example
You send a newsletter from you@yourbusiness.com. Your server signs the message with DKIM. The receiving server fetches your public key from DNS, checks the signature and sees that the mail really is from you and wasn't changed along the way. The result: more trust and a greater chance of reaching the inbox.
Why DKIM matters
DKIM strengthens trust in your email without your recipient noticing a thing; the check happens automatically in the background. For you, a correct DKIM record means your mail is less likely to be flagged as spam and that no one can quietly change the content and still use your name. The key is refreshed from time to time, but with a hosted service that usually happens automatically.
Related terms
- DKIM explained
- What is DMARC?
- Back to the glossary
Ready to set it up? DKIM explained walks you through it step by step.