Tools

SPF / DKIM / DMARC Checker

Check whether a domain publishes core email-authentication records and inspect the returned TXT values.

Email Authentication Flow

How SPF, DKIM, and DMARC fit together

  1. SenderMessage claims to come from a domain.
  2. SPF / DKIM checksReceiver checks sending IP authorization and cryptographic signature when present.
  3. DMARC alignment and policyReceiver checks whether SPF or DKIM aligns with the visible From domain and reads the domain policy.
  4. Receiver actionDeliver, quarantine, reject, or report based on policy and local filtering.

This diagram is educational. Mail authentication improves trust signals, but it does not prove that a message is safe.

DMARC Builder

Generate a starter DMARC record without pretending it is universal

Use checker above
Advanced options

Advanced options can affect legitimate mail. Test known senders before enforcement.

Generated example

Customize before publishing


            

            

          

        

      

    

    

      

        
Examples
Copyable starter records with clear caveats

        

          

            
DMARC monitoring example
Start with visibility

            
_dmarc.example.com TXT "v=DMARC1; p=none; rua=mailto:dmarc-reports@example.com; pct=100"

            
Example only. Replace the domain and reporting address. Monitoring does not block spoofed mail.

          

          

            
SPF example
Authorize known senders only

            
example.com TXT "v=spf1 include:_spf.example-mail-provider.com -all"

            
Example only. Replace the include with your real mail provider and avoid multiple SPF records.

          

          

            
Comparison
SPF, DKIM, and DMARC roles

            

              
SPFChecks whether a sending IP is authorized for the envelope domain.

              
DKIMChecks whether signed message content matches a domain-controlled key.

              
DMARCChecks alignment with the visible From domain and requests receiver handling.