Email headers analyzer.
Paste raw email headers from any message. We parse the Received chain hop-by-hop, extract SPF, DKIM, and DMARC results from Authentication-Results, surface spam scores, and flag suspicious patterns before they reach your inbox.
Headers are the only ground-truth record of what happened to your email. When a campaign lands in spam, the fix is almost always there — wrong Return-Path, missing DKIM signature, SPF failure on a forwarding hop, or a routing path that adds latency that the receiver penalizes. To get headers in Gmail: open the message, click the three dots, then "Show original". In Outlook: File → Properties → Internet headers.
Green: SPF, DKIM, and DMARC all pass with aligned domains. Amber: at least one auth check failed or aligned weakly. Red: auth failed or spam flags present.