One-click presets
SEC
Mail Security Check
Score out of 10 — combines SPF, DMARC, DKIM, MX and blacklist reputation into a single overall rating with per-record findings and fixes.
SPF
Anti-Spoofing Audit
Focused on whether your domain can be forged. Weighted heavily toward DMARC enforcement and SPF strictness. Gives a clear verdict.
IN
Inbound Mail Health
Verifies you can receive mail: MX, live SMTP connection, STARTTLS handshake, reverse DNS and DNSBL listing on your MX IPs.
Individual tools
MX LookupSorted by priority + resolved IPs
SPFMechanism breakdown + DNS lookup count
DMARCTag-by-tag policy report
DKIMCustom selector or ~30 common ones
All DNSA/AAAA/MX/NS/TXT/CNAME/SOA/CAA/SRV
Reverse DNSPTR + FCrDNS verification
Blacklist14 public DNSBLs
SMTP TestBanner + EHLO + STARTTLS probe
Open RelayTests external RCPT acceptance
WHOISDirect port-43 lookup
Header AnalyzerHops + delays + auth
Why use MX Tool Check?
MX Tool Check is a free email diagnostics suite that helps domain owners, sysadmins and security teams verify their mail configuration end-to-end. Every check runs from our servers using direct DNS queries and live SMTP connections — no API keys, no rate limits, no third-party data collection.
SPF Validator
Mechanism breakdown, 10-lookup RFC 7208 limit checker, qualifier strictness audit.
DMARC Inspector
Policy parse, alignment hints, reporting coverage and enforcement progression advice.
DKIM Checker
Auto-detects 30+ common selectors or pinpoints custom ones, validates the public key.
Blacklist (DNSBL)
Cross-checks your MX IPs against 14 major reputation blocklists with per-RBL pass/fail.
SMTP & STARTTLS
Live banner, EHLO extensions, STARTTLS handshake and TLS metadata inspection.
Reverse DNS
PTR lookup with forward-confirmed reverse DNS (FCrDNS) validation for deliverability.
