DNS-based checks

SPF, DKIM and DMARC Checker

Enter a domain to check public email authentication records. This sends only the domain name and optional DKIM selectors to the DNS lookup API, not any pasted email headers or bounce messages.

Sender authSPF, DKIM, DMARC alignment basics

Inbound hintsMX present / missing

Domain

DKIM selectors Optional

DKIM records use selector._domainkey.domain. You can enter one or more selectors, separated by commas, spaces or new lines. Microsoft 365 commonly uses selector1, selector2.

Your email data stays in your browser. DNS checks use public domain records. Do not paste private email headers into this tool.