MailHealth
Choose an amount before the secure payment page opens.

MailHealth

Email authentication checks without mandatory signup.

Check SPF, DKIM, DMARC, MX, DNSBL reputation, SMTP reachability and raw headers with clear antiabuse limits and no account requirement.

Domain health report

Run one email health report across the signals receivers inspect.

Check SPF, DKIM, DMARC, MX, blacklist sample, SMTP reachability and optional headers in one point-in-time report.

No saved domainsRate-limited API callsNo SMTP message sentHeaders parsed locally
Headers stay in the browser and are never sent to the MailHealth API.
Unified score--Report status

Report checklist

Run a report to score visible authentication, DNS, reputation, SMTP and header signals.

Headers stay local; DNS, DNSBL and SMTP checks are rate-limited, point-in-time diagnostics.

AuthenticationLive check

SPF Checker

Find the SPF TXT record for a domain and flag risky all, duplicate or lookup-heavy policies.

Free check
One point-in-time SPF lookup with duplicate, all-mechanism and lookup-count warnings.
Optional account features
Ongoing authentication monitoring, diff history, alerting, batches and API access.
Open check
AuthenticationLive check

DKIM Checker

Check a selector._domainkey TXT record and confirm that a DKIM public key is published.

Free check
One selector lookup with key-present, version and tag summary.
Optional account features
Selector inventory, rotation reminders, key-length policy checks, reports and API batches.
Open check
AuthenticationLive check

DMARC Checker

Inspect the _dmarc TXT record and identify policy, alignment and reporting readiness.

Free check
One DMARC TXT lookup with policy, pct and aggregate-report presence.
Optional account features
DMARC aggregate report ingestion, trend history, alerts, teams and white-label reports.
Open check
DNS recordsLive check

MX Checker

Inspect mail exchanger priority, host shape and public resolution before debugging delivery.

Free check
One MX lookup with priority sort and public-resolution guard.
Optional account features
MX change monitoring, incident history, alert routing and multi-domain batch checks.
Open check
ReputationLive check

Blacklist Check

Run a small DNSBL sample against public mail-related addresses with strict query limits.

Free check
Small DNSBL sample for a limited number of public IPv4 addresses.
Optional account features
Reputation monitoring, alerting, provider-specific reports, batches and white-label exports.
Open check
SMTP transportLive check

SMTP Check

Test bounded TCP reachability to a domain mail exchanger without sending a message.

Free check
One MX-based TCP probe on allowed SMTP ports with no EHLO, recipient or message sending.
Optional account features
Uptime monitoring, incident timelines, alerting, multi-region checks and status reports.
Open check
Message headersLive check

Header Analyzer

Parse raw message headers locally to summarize SPF, DKIM, DMARC and alignment clues.

Free check
Local header parsing for one message with no backend call and no browser storage.
Optional account features
Saved investigations, team comments, report exports, alert delivery and API analysis.
Open check

Operating principles

Useful free diagnostics

A domain owner can inspect core email records and headers before creating an account.

Bounded probes

DNS, DNSBL and SMTP checks use public-host validation, short timeouts, cache and rate limits.

No PII analytics

Domains, mail hosts, headers, message IDs and results are never sent to analytics events.

Support

The free tool stays available without signup. Bookmark this page, share it when useful or send corrections from the contact page.

  • Useful result first
  • No signup required
  • Promotions kept separate
Choose an amount before the secure payment page opens.