Generate and validate SPF, DMARC, DKIM, MX, and BIND zone files.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Specify your domain name in the domain settings.
Select email providers, custom includes, and DMARC enforcement policies.
Copy the formatted TXT record or complete BIND zone file into your DNS provider.
DMARC prevents attackers from sending phishing emails from your domain name by instructing recipient mail servers to reject unauthorized senders.
Zero-egress companion tools in the Security & Network suite
Audit CSP, HSTS, X-Frame-Options, and security headers with OWASP grading (A+ to F).
Measure cryptographic randomness, Shannon entropy (0-8 bits/byte), Chi-square test, and byte distributions.
Generate secure RFC 6238 Base32 TOTP secret keys and standard otpauth:// URIs for Google Authenticator.
Construct and validate HTTP CSP headers and meta tags.
