Free tool

DKIM checker

Enter your domain. We look up its DKIM record across common selectors, show which selector publishes a key, and flag the issues that get mail rejected: no key, an empty key, or a key that is too weak. No signup, no email required.

DKIM is one of four records

DKIM signs each message, but SPF lists your senders and DMARC tells receivers what to do when they fail. The full audit checks all four plus TLS, reverse DNS and blocklists.

Run the full free audit

Prefer to read first? SPF vs DKIM vs DMARC · How to create a DMARC record · Check all four records · MX checker · IP blocklist checker · Email header analyzer