Private browser tool
Did this email really pass DKIM and DMARC?
Paste the full message header. MX Audit reads the receiver’s SPF, DKIM, and DMARC results, shows the authenticated domains, and creates a shareable evidence brief—without uploading the header.
01 · Paste
Full email header
Everything is parsed in this browser tab. If you paste a complete message, MX Audit stops at the first blank line and discards the body.
02 · Evidence
Your authentication result appears here.
The tool reports what the receiving system evaluated. It does not send a test message or access a mailbox.
Interpretation boundary
A header is evidence, not proof by itself.
RFC 8601 warns that Authentication-Results are reliable only inside the trust boundary of the receiver that added them. A pasted header can be edited, forwarded mail can change SPF, and one passing sample does not inventory every service using a domain.