No sign-up
Email Header Analyzer
Check SPF, DKIM, DMARC and mail path from raw headers. No sign-up.
This is a free online email header analyzer for security and IT teams: paste raw headers to see authentication results and sender path. We don't store your data.
Analyze email headers
Paste the full message headers (View source / Show original / Download .eml headers only). We parse folded lines, build a Summary, Received hop table, Forefront / Microsoft antispam fields, and other headers (similar to Microsoft Message Header Analyzer). Nothing is stored on our servers beyond this request.
Why analyze email headers?
Headers show how an email was routed and whether authentication (SPF, DKIM, DMARC) passed. That helps you troubleshoot bounces, spot phishing or spoofing, and improve your own domain's configuration for sending mail.
FAQ
Where do I find email headers?
In Gmail: open the message → three dots → Show original. In Outlook: File → Properties → Internet headers. In Apple Mail: View → Message → Raw Source. Copy the full header block and paste it here.
What are SPF, DKIM, and DMARC?
SPF and DKIM help verify that the sending server is allowed to send for the domain. DMARC tells receivers what to do when those checks pass or fail. Together they reduce spoofing and improve deliverability.
Do you store the headers I paste?
No. Headers are sent to our server only for the analysis request and are not stored or logged.