Free online tool
DKIM Checker
Inspect one known DKIM selector. Find it in your provider settings or a message’s DKIM-Signature header.
Your result will appear here.
Related tools
DNS Toolkit
Look up A, AAAA, CNAME, MX, TXT, NS, CAA, and SOA records with available TTLs.
DNS Propagation Checker
Compare Cloudflare and Google Public DNS observations. Resolver disagreement can reflect normal caching.
SPF Checker
Inspect SPF policies, syntax, include recursion, and DNS lookup limits without sending email.