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  • SSL Certificate Checker
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Email authentication
  • SPF Record Checker
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Website security
  • Security Headers Checker
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  • What Is My IP Address
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Log inStart free
  • MonitoringCertificate & Domain MonitorDaily checks of TLS certificates, domain registration and DNS, with alerts when a renewal fails.
  • AssessmentSecurity AssessmentA passive security report for a domain you own: TLS, DNS, email authentication, headers and registration.
Free tools
Start hereDomain Health Check
Domain
  • Bulk Domain Expiry Checker
  • RDAP Domain Lookup
  • WHOIS Lookup
SSL / TLS
  • SSL Certificate Checker
  • Bulk SSL Expiry Checker
  • 47-Day Certificate Lifetime Calculator
  • Certificate Lifetime Readiness
  • Post-Quantum TLS Checker
DNS
  • DNS Lookup
  • MX Lookup
  • CAA Record Checker
  • DNS Propagation Checker
  • TXT Record Lookup
  • NS Lookup
  • CNAME Lookup
  • Reverse DNS Lookup
Email authentication
  • SPF Record Checker
  • SPF Record Generator
  • DMARC Record Checker
  • DMARC Record Generator
  • DKIM Record Checker
  • Email Sender Requirements Checker
Website security
  • Security Headers Checker
Network & IP
  • What Is My IP Address
  • Subnet Calculator
All free tools →
PricingDocsGuides
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  1. Home
  2. /Free tools
  3. /Email authentication

Free Email authentication tools

Check and build the SPF, DKIM and DMARC records that stop your domain being spoofed.

Authentication checks

  • SPF Record Checker

    The full include tree and the DNS-lookup count against the limit of 10.

  • DMARC Record Checker

    Policy, alignment, report addresses and the mistakes that stop reports arriving.

  • DKIM Record Checker

    Find DKIM keys by selector and check their type and size.

Deliverability

  • Email Sender Requirements Checker

    One verdict for the Gmail, Yahoo and Outlook bulk-sender rules: SPF, DKIM, DMARC and the rest.

Record generators

  • Runs in your browser

    SPF Record Generator

    Build a valid SPF record from your providers and server IPs. Runs in your browser.

  • Runs in your browser

    DMARC Record Generator

    Create a DMARC record with the right policy and reporting. Runs in your browser.

Other categories

  • Domain
  • SSL / TLS
  • DNS
  • Website security
  • Network & IP
  • All free tools →
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Renewal-failure alerts for TLS certificates and domain registrations.

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Free tools

  • Domain Health Check
  • SSL Certificate Checker
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  • DMARC Record Checker
  • Security Headers Checker
  • DNS Lookup
  • All free tools →

Tool categories

  • Domain
  • SSL / TLS
  • DNS
  • Email authentication
  • Website security
  • Network & IP

Resources

  • Documentation
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