365Fanatic / Tools / Email header analyzer

Email header analyzer

Paste a message's headers and see the route it took, where the delay was, whether SPF, DKIM and DMARC passed, and what Microsoft 365 made of it.

Everything happens in your browser. The headers are not sent to 365Fanatic or anyone else and are stored nowhere; we only count how often the tool is used.

Where do I find the headers?
  • New Outlook and Outlook on the web: open the message, … (More actions) > View > View message details.
  • Classic Outlook: open the message, File > Properties > Internet headers.
  • Gmail: ⋮ (More) > Show original.
  • Apple Mail: View > Message > All Headers.

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