EmailHealth

Email Health Checker

Test your domain's email deliverability and security — SPF, DKIM, DMARC, MX, TLS, reverse DNS and blacklist status — in seconds.
SPF
DKIM
DMARC
MX Records
Blacklists

Free email health checker

The ShowDNS Email Health Checker runs a complete, read-only audit of a domain's email configuration and grades it from A+ to F. In a single test it checks SPF, DKIM and DMARC authentication, MX records and mail provider, STARTTLS, MTA-STS and TLS-RPT transport security, reverse DNS (PTR) and forward-confirmed reverse DNS, blacklist reputation, and BIMI brand signals — then highlights the issues that hurt deliverability and how to fix them. It is free, needs no signup, and works on any public domain.

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Get recommendations and solutions to fix email deliverability problems and configuration issues
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Check DMARC policy records for email authentication, reporting, and policy enforcement
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Find mail exchange (MX) records for email server configuration and priority
Domain Health Checker
Full domain audit report covering DNS, DNSSEC, WHOIS, SSL/TLS, security headers, CDN, IPv6, HTTP/2 & HTTP/3, blacklists, DNS propagation and email authentication

Email Health Checker — Frequently Asked Questions

Common questions about email health and deliverability
6 Q&A

An email health check is a consolidated audit of everything that affects a domain's email deliverability and security — SPF, DKIM and DMARC authentication, MX records, STARTTLS and MTA-STS transport encryption, reverse DNS (PTR), BIMI brand signals and blacklist reputation. ShowDNS combines all of these into a single graded report.

Yes. The email health checker is completely free, requires no signup, and you can run it on any public domain as many times as you need.

It checks SPF, DKIM and DMARC authentication, MX records and mail provider, STARTTLS / MTA-STS / TLS-RPT transport security, reverse DNS (PTR) and forward-confirmed reverse DNS, blacklist and reputation across major DNSBLs, and BIMI brand logo readiness.

Each category is scored and the results are combined into an overall score that maps to a letter grade from A+ (95+) down to F (below 60), giving you a single measure of your domain's email health.

Yes. You can enter a full email address and the checker will automatically test the domain part after the @ sign.

No. The email health checker is completely read-only. It only performs standard DNS, SMTP and TLS lookups to evaluate the domain and never modifies any records.