Paste raw email headers and instantly see the full routing path, SPF/DKIM/DMARC results, delivery time, sender IP, and any spam scores. Diagnose delivery issues in seconds.
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Email headers are metadata attached to every email — invisible to regular recipients but essential for diagnosing deliverability problems, tracing spam, and verifying authentication. They're read bottom-to-top, with the oldest entries at the bottom.
Gmail: Open the email → "⋮" menu → "Show original". Outlook: File → Properties → Internet headers. Apple Mail: View → Message → Raw Source.
Each mailserver that processes the email adds a "Received:" line. The bottom one is from the original sender, the top one is from the final destination. Delays between hops indicate slow servers.
Added by the receiving server, this shows if SPF, DKIM, and DMARC passed or failed. SPF = sender IP authorized. DKIM = message signed. DMARC = policy enforced.
X-Spam-Score, X-Spam-Status (SpamAssassin), and X-Forefront-Antispam-Report (Microsoft) indicate how likely the email was considered spam before reaching your inbox.
Lume sets up SPF, DKIM, and DMARC for you — and keeps your reputation clean automatically.