Is it safe to generate a DKIM private key in an online generator?

Yes, with KaijuVerifier's generator. Unlike server-side generators that create your private key on their backend, our generator uses your browser's native Web Crypto API (window.crypto.subtle.generateKey). Your private key is generated 100% inside your device's RAM and is never transmitted over the internet.

Should I choose a 2048-bit or 1024-bit DKIM key?

Always choose 2048-bit RSA unless your DNS provider does not support TXT records longer than 255 characters. If your DNS interface requires splitting long TXT strings into 255-character chunks, enable the 'Split into 255-char DNS chunks' toggle above.

⚙️ SPF Generator 🔑 DKIM Generator 🔒 DMARC Generator 🔍 Check Live DKIM

100% IN-BROWSER WEBCRYPTO · RSA-2048 · ZERO SERVER TRANSMISSION

Free DKIM Key & DNS Record Generator

Generate a cryptographic 2048-bit or 1024-bit RSA keypair directly in your browser using the native Web Crypto API. Copy your ready-to-publish v=DKIM1 DNS TXT record and download your PEM private key for Postfix, OpenDKIM, Exim, or Haraka.

Sending Domain

DKIM Selector

RSA Key Strength

Split DNS TXT value into 255-character quoted chunks (BIND / AWS Route53 format)

1. Publish this DNS TXT Record

Host / Name: mail2026._domainkey.example.com · Type: TXT

Generating 2048-bit RSA keypair...

2. Private Key (PKCS#8 PEM — Keep Secret on Your Mail Server)