Free tool
DKIM checker.
Enter a domain and selector to check DKIM record configuration.
What is DKIM?
DomainKeys Identified Mail adds a cryptographic signature to outgoing emails, proving they came from an authorized sender.
Why it matters
Without DKIM, receiving servers cannot verify message integrity. This increases spam placement risk.
Common selectors
Google Workspace: google. Outlook: selector1/selector2. Mailgun: smtp. SendGrid: s1.