Authenticate outbound mail
Start with records receivers use to trust a sender domain.
Choose an amount before the secure payment page opens.
Email authentication and domain health
Check a domain's email health before changing DNS.
Start with SPF, DKIM, DMARC, MX, blacklist, SMTP and header checks from one public page. The free flow gives a point-in-time answer before any account path.
Choose an email diagnostic
MailHealth follows the common toolbox model: enter a domain, choose the exact check, read the signal and fix the responsible DNS or mail setting.
Check receiving path
Review exchanger records and SMTP reachability before blaming content or reputation.
Investigate evidence
Compare reputation signals with pasted message headers when a real message looks suspicious.
Start with the checks senders expect
Open SPF, DKIM, DMARC, MX, blacklist, SMTP or header analysis directly. Each page keeps the free answer first and the limits below it.
AuthenticationSPF CheckInspect the SPF TXT record and flag duplicate, permissive or lookup-heavy policies.Open checkAuthenticationDKIM CheckCheck a selector._domainkey record and confirm that a public key is visible.Open checkAuthenticationDMARC CheckRead policy, alignment and reporting tags from the _dmarc TXT record.Open checkDNS and MXMX CheckReview mail exchanger priority and public host resolution before delivery debugging.Open checkReputationBlacklist CheckRun a bounded DNSBL sample for public mail-related addresses.Open checkSMTPSMTP CheckTest bounded TCP reachability to a selected domain mail exchanger.Open checkHeadersHeader AnalysisParse raw message headers locally for SPF, DKIM, DMARC and alignment clues.Open check
Point-in-time checks
Public tools inspect current records, selected public hosts or pasted headers. Recurring alerts, history, report ingestion, exports and team tools are separate account features.
Targets stay out of analytics
Domains, selectors, mail hosts, headers and results are not sent to product analytics events. Header analysis runs in the browser.
All published MailHealth checks
Move between authentication, DNS routing, reputation, SMTP reachability and message header analysis.
AuthenticationSPF CheckInspect the SPF TXT record and flag duplicate, permissive or lookup-heavy policies.Open checkAuthenticationDKIM CheckCheck a selector._domainkey record and confirm that a public key is visible.Open checkAuthenticationDMARC CheckRead policy, alignment and reporting tags from the _dmarc TXT record.Open checkDNS and MXMX CheckReview mail exchanger priority and public host resolution before delivery debugging.Open checkReputationBlacklist CheckRun a bounded DNSBL sample for public mail-related addresses.Open checkSMTPSMTP CheckTest bounded TCP reachability to a selected domain mail exchanger.Open checkHeadersHeader AnalysisParse raw message headers locally for SPF, DKIM, DMARC and alignment clues.Open check