Email deliverability tools
Free checkers and record generators for SPF, DKIM, DMARC, MX, TLS, and blacklists.
Checkers
- MX lookupLook up MX records for any domain. Instant, free, plain English.
- SPF CheckerCheck a domain's SPF record — syntax, lookup count, and common issues. Instant, free, plain English.
- DKIM CheckerCheck a DKIM public key for a given domain and selector. Instant, free, plain English.
- DMARC CheckerCheck a domain's DMARC policy — what it enforces, what's missing, and where it aligns. Instant, free, plain English.
- Blacklist lookupCheck whether your mail-server IPs are listed on email blacklists. Instant, free, plain English.
- TLS CheckInspect both your domain's outbound submission server TLS and the inbound TLS posture announced via DNS (MTA-STS + TLS-RPT). Instant, free, plain English.
- Header AnalyzerPaste raw message headers. See the delivery path, per-hop delays, and the SPF / DKIM / DMARC verdicts the receiving server recorded. Headers never leave your browser.
- DMARC Report AnalyzerUpload or paste a DMARC aggregate (RUA) report. See pass rates, per-source breakdowns, and actionable findings. Your report never leaves your browser.
- TLS-RPT Report AnalyzerPaste or upload an RFC 8460 SMTP TLS (TLS-RPT) report. See per-policy success and failure session counts, an aggregate TLS success rate, and plain-English failure reasons. Your report never leaves your browser.
- Reverse DNS LookupLook up the PTR record for an IP and confirm it forward-resolves back to the same address. Instant, free, plain English.
- DNS Propagation CheckerSee whether a DNS change has taken effect yet. Compare one record across major public resolvers and the domain’s own authoritative nameservers. Instant, free, plain English.
- DNS LookupEnter a domain to see all of its DNS records at once — addresses, mail servers, text records, nameservers, aliases and more — read directly from the domain’s own authoritative nameservers rather than a resolver cache.
- Email Deliverability TestSend one email to a one-time address and see the real SPF, DKIM, DMARC, and ARC results the receiving server recorded — an email tester and email spam test in one, with no headers to copy and no guessing.
- Phishing URL CheckerPaste a link to see the structural red flags in the address itself and whether Google Safe Browsing has it listed. A clean result is never a promise that a link is safe, and this page is honest about what it cannot see.
Record generators
- SPF GeneratorBuild a valid SPF record in seconds. Pick your senders, set the policy, copy the TXT record.
- DMARC GeneratorBuild a DMARC record in seconds. Pick a policy, add a reporting address, copy the TXT record for _dmarc.
- DKIM GeneratorGenerate a DKIM keypair in your browser. Copy the public DNS record; the private key never leaves this page.
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