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Email Auth Checker

Enter your domain to check its SPF, DKIM, and DMARC records. Missing or misconfigured email authentication records cause legitimate emails to be rejected or marked as spam by recipient mail servers.

How to check email authentication for a domain

  1. Enter the domain — Type the domain you want to check (e.g. example.com) — not the email address, just the domain.
  2. Click "Check" — The tool queries DNS and retrieves SPF, DKIM and DMARC records.
  3. Read the results — Each record is shown alongside a pass / fail / warning status with an explanation of any issues found.
  4. Fix any problems — If SPF is missing, add a TXT record in your DNS. For DMARC, start with p=none (monitor mode) before moving to p=quarantine or p=reject.

Frequently asked questions

What is SPF?

Sender Policy Framework (SPF) is a DNS TXT record that lists which mail servers are authorized to send email for your domain. Without it, spammers can send email that appears to come from you.

What is DKIM?

DomainKeys Identified Mail (DKIM) adds a cryptographic signature to outgoing emails. Receiving mail servers verify the signature against a public key in your DNS, confirming the email was not tampered with in transit.

What is DMARC?

Domain-based Message Authentication, Reporting and Conformance (DMARC) ties SPF and DKIM together. It tells receiving servers what to do when email fails authentication — none (monitor), quarantine, or reject — and where to send reports.

Do I need S/MIME as well?

SPF / DKIM / DMARC protect the mail transport layer. S/MIME certificates add end-to-end encryption and digital signatures at the message level, giving recipients proof that the email came from you and was not altered. They work together for maximum protection.

What this tool checks

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SPF record

Sender Policy Framework — lists which servers are authorized to send email for your domain. Missing SPF is a common cause of email rejection.

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DKIM record

DomainKeys Identified Mail — a cryptographic signature attached to outgoing email. Verifies the email was not modified in transit.

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DMARC record

Domain-based Message Authentication — tells recipient servers what to do with emails that fail SPF or DKIM checks. Critical for anti-spoofing protection.