Free mail security check
Free DMARC checker: test SPF and DKIM.
See what your domain publishes in DNS and get one plain-English sentence on its current email authentication state.
What the check covers
Three DNS signals, one clear result.
What does a DMARC checker test?
It finds the TXT record at _dmarc.your-domain, validates the policy and shows whether it monitors, quarantines or rejects unauthenticated mail.
What does the SPF check include?
It reads the SPF record, follows its DNS dependencies and counts the lookups against SPF’s limit of 10.
Why is a DKIM selector optional?
A DKIM key lives at a selector-specific address. Enter the selector supplied by your email platform to verify that public key without guessing.
Does a healthy result mean p=reject is safe?
Not by itself. DNS cannot reveal every service that sends as your domain; DMARC report evidence is needed before enforcement.
A DNS check is the starting point
Know what will break before you enforce DMARC.
SenderLedger identifies every service sending as your domain, explains SPF and DKIM alignment failures, tracks the fixes and verifies when moving to p=reject is safe.