SuperTool

Queries go straight to the domain's authoritative nameservers, so changes show up instantly.

Email HealthScore a domain 0–100: MX, SPF, DKIM, DMARC, MTA-STS, BIMI, rDNS, blacklists, reachability. Blacklist CheckCheck an IP or host against the major DNS blacklists (RBLs). SMTP DiagnosticsConnect from outside: banner, rDNS, STARTTLS, certificate, open relay, timings. SPF / DMARC / DKIMLook up and validate the authentication records for a domain. DNS CheckDelegation, nameserver health, SOA values, glue and dispersion — parent vs child. DNS PropagationCompare answers from Cloudflare, Google, Quad9, OpenDNS and the authoritative servers. Header AnalyzerPaste an email's headers to see the hop-by-hop route, delays and SPF/DKIM/DMARC results. Monitoring & AlertsGet emailed when DNS changes, a mail server goes down, a cert nears expiry or an IP gets blacklisted.