Free Tool

DKIM Key Generator

Generate a 2048-bit RSA DKIM key pair entirely in your browser — nothing is sent to any server. Copy the public key for DNS, and download the private key for your mail server.

Keys are generated locally — your private key never leaves this page

Key settings

The domain you're setting up DKIM for. Used to preview your full DNS record name.

domain

An identifier for this key — part of the DNS record name. Pick a provider preset or type a custom value.

Test mode t=y

Signals to receivers that this key is in testing. Mail may still be signed, but failures are treated leniently. Uncheck for production.

Browser-only generation

RSA key pairs are created using the Web Crypto API. Nothing is transmitted to any server.

Ready-to-paste DNS record

The public key is formatted as a TXT record value you can paste directly into your DNS provider.

PEM private key download

Download the private key as a .key file ready to configure in Postfix, Google Workspace, or any compatible mail server.

DKIM signed — now keep it monitored

Mailflo continuously monitors your DKIM, SPF, and DMARC records across all your sending domains and alerts you instantly when something breaks or drifts.

See Mailflo plans