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© Nutter Toolsnutter.tools
  1. Home
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  3. Email headers
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Email header analyzer

Paste raw email headers and see the From and Return-Path, each Received hop with its delay, and the SPF, DKIM, DMARC and ARC results.

This tool is in beta

Still being tested. If a result looks wrong, tell us.

Report a problem

Paste a header block

The From and Return-Path pair, every Received hop with its delay, and the recorded SPF, DKIM, DMARC, and ARC verdicts appear as you type.

Headers can be forged. Any relay in the chain can write whatever From, Received, or Authentication-Results line it likes, so this page is analysis, not proof. The SPF, DKIM, DMARC, and ARC outcomes are read out of the headers exactly as an upstream server recorded them; they are not re-verified against DNS here. A mismatch between From and Return-Path is common with mailing lists and forwards, and is not evidence of wrongdoing on its own.

Raw headers

Up to 100,000 characters; the message body is dropped

Everything runs in this tab. Nothing you paste is sent anywhere.

More network tools

  • HTTP timing probe
All network tools

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