Email authentication guide
Check whether your domain is protected from spoofing
SPF, DKIM, and DMARC work together to help receiving mail systems distinguish authorized senders from forged messages. Use this email security checker to identify missing records, weak policies, and configuration gaps that can damage deliverability or enable impersonation.
What SPF, DKIM, and DMARC do
SPF publishes which mail servers may send for a domain. DKIM adds a cryptographic signature to messages, while DMARC tells receivers how to handle messages that fail authentication and where to send aggregate reports.
- SPF authorized-sender policy
- DKIM signing and selector records
- DMARC alignment and enforcement
- Spoofing and deliverability risk
A practical remediation path
Inventory every legitimate sender first, publish SPF without exceeding DNS lookup limits, enable DKIM for each provider, and begin DMARC with monitoring. After reviewing reports and correcting legitimate failures, move toward quarantine or reject when the domain is ready.
Passive checks only
The checker performs passive DNS lookups and does not send email or attempt to access your systems. Results are a starting point: confirm provider-specific setup, monitor DMARC reports, and retest after every DNS or mail-platform change.