DNS Zone & Security Record Builder
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. No data is ever transmitted across the network.
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.
How to Use DNS Zone & Security Record Builder
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.
Frequently Asked Questions
Why is a DMARC policy necessary?
DMARC prevents attackers from sending phishing emails from your domain name by instructing recipient mail servers to reject unauthorized senders.
Related Security & Network Tools
View all →Split master passwords into M-of-N threshold shares with GF(256) math.
Generate cryptographically secure 12, 18, or 24-word seed phrases.
Calculate network address, broadcast, usable host IP range, and masks.
Derive secure keys with customizable iterations, salts, and SHA hashes.