Free tool

SPF, DKIM and DMARC Checker

Check a domain's email authentication, see exactly how many of the 10 allowed SPF DNS lookups it uses, and build new SPF and DMARC records.

Also scan common DKIM selectors

Uses public DNS only. Nothing is stored; results are cached for 15 minutes. DKIM selectors cannot be listed publicly, so the scan tries about 20 common names. Find your real selector in the s= value of a message's DKIM-Signature header.