DKIM Generator

DKIM Generator is a focused domain security tool that outputs the exact DNS TXT value required to publish a DKIM public key for a given selector and domain. It supports RSA-based signing (rsa-sha256) and can generate a new 2048-bit key pair or accept an existing private key, then derives the corresponding public key for publication. The output is a ready-to-paste TXT record value that you add to the DNS zone as selector._domainkey.domain. The tool follows RFC 6376 standards and is designed for reliability, auditability, and straightforward key rotation.
Inputs are domain, selector, algorithm (default rsa-sha256), optional key_size, and an optional private_key. If private_key is omitted, the tool can generate a new key pair. It then computes the public key, encodes it in base64, and assembles the DNS TXT value with the v=DKIM1; k=rsa; p= syntax. The tool also validates syntax constraints and flags common issues such as overly long records or invalid characters before export.
Use cases include onboarding new domains, rotating compromised or expired keys, and preparing multiple selectors for key rollover. The generated value is a drop-in DNS TXT record, suitable for mail providers and DMARC configurations. By centralizing key generation, rotation planning, and DNS formatting, the tool reduces manual errors and accelerates secure mail delivery for organizations of any size.