Free Email Security Tools
Check and validate your domain's email authentication configuration. All tools are free, no account required.
DNS Record Checkers
Enter any domain to instantly check its email authentication records. Each tool validates the DNS configuration and reports issues with clear explanations.
DMARC Checker
Verify your DMARC record syntax, policy strength, alignment settings, and reporting configuration.
Check nowSPF Checker
Validate SPF records, count DNS lookups against the 10-lookup limit, and detect authorized email providers.
Check nowDKIM Checker
Verify DKIM keys across common selectors, check key strength, and detect weak 1024-bit keys.
Check nowMTA-STS Checker
Validate MTA-STS DNS records, HTTPS policy files, mode configuration, and MX record alignment.
Check nowBIMI Checker
Check BIMI records, logo availability and format, and VMC certificate authority.
Check nowTLS-RPT Checker
Validate TLS-RPT DNS records, reporting destinations, and STARTTLS support on your mail servers.
Check nowMore Tools
DMARC Alignment Tester
Send a real test email and verify that SPF, DKIM, and DMARC alignment are properly configured on your sending infrastructure.
Try itSPF Record Builder Guide
Step-by-step guide to writing your SPF record, with copyable include values for common email providers and the 10-lookup limit explained.
Try itTLSA Record Generator
Generate DANE TLSA records from the certificate your mail servers actually serve. No certificate pasting required.
Try itNeed continuous monitoring?
These tools give you a one-time check. MailShield rechecks every domain you add every 2 hours, with alerts, DMARC report processing, and security scoring. Free for 1 domain.