First public sender IPv4 found in Received headers.
FREE EMAIL DIAGNOSTICS TOOL
Turn raw email headers into a readable delivery report.
Paste a message header and inspect authentication, sending IPs, routing hops, delays, DKIM details, Return-Path, unsubscribe support and likely sending infrastructure.
SPFDKIMDMARCSending IPRoute DelaysRaw Headers
PASTE HEADERS
Email header source
Paste the raw header section from Gmail, Outlook, webmail, an SMTP log or another email client.
Private browser-side analysis: the pasted header is processed locally on this page and is not uploaded by this tool.
AUTHENTICATION STATUS——
SPF—
DKIM—
DMARC—
Best-effort inference from routing hostnames and headers.
Number of Received header entries.
Time between earliest and latest parseable hop timestamps.
Authentication
Results reported by the receiving system.
Message identity
Key message and envelope fields.
DKIM & list headers
Signing identity and unsubscribe information.
Delivery route
Received headers ordered as they appear in the message.
Header inventory
Frequently useful diagnostic headers found in this message.
Raw header
Original pasted content.
How to get full email headers
In Gmail use Show original. In Outlook use View message details or View source. Paste the header block here, not just the visible From/To/Subject lines.
Authentication result note
This browser-only tool reports SPF, DKIM and DMARC verdicts already present in Authentication-Results or ARC headers. It does not independently re-run cryptographic DKIM verification or DNS authentication checks. Use the Email Health Checker and Deliverability Analyzer for complementary live diagnostics.