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SECURITY

Email Header Analyzer

Paste an email header to inspect From, To, Subject, Received hops, Authentication-Results, SPF, DKIM, DMARC, ARC, and other common fields locally.

Tool statusRuns in your browser
Preview
Or drop a text filechoose a file
.txt, .eml, .log · up to 2.0 MB. Read in your browser, never uploaded.

Summary

Paste a message header to analyze it.


Received route

N/A


Reported authentication

N/A

SPF, DKIM, DMARC, and ARC values shown here are reported by headers. ProntoUso does not revalidate them.

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Privacy and processingRuns locally in your browser. This tool does not upload your input.

What is Email Header Analyzer?

Paste a raw email header to organize common fields, Received hops, and authentication results reported by mail servers.

UNDERSTAND THE TOOL

How to analyze email headers

Received route

Received headers are usually added at the top as a message moves between servers. The analyzer reverses them into an easier chronological route from earliest to latest hop.

Authentication results

SPF, DKIM, DMARC, and ARC values are read from headers such as Authentication-Results and Received-SPF. The tool reports what those headers say; it does not re-run DNS or cryptographic validation.

Common uses

  • Review delivery paths during support troubleshooting.
  • Find Message-ID, Return-Path, or Reply-To quickly.
  • Read authentication results without digging through folded headers.

What the warning means

The analyzer can read reported SPF, DKIM, DMARC, and ARC results, but it does not query DNS or verify DKIM signatures again.

Header parsing notes

Raw headers can contain email addresses, message IDs, IPs, and server names. They are parsed locally, but clear the field before switching tasks on a shared screen.

Frequently Asked Questions

Does this validate SPF, DKIM, or DMARC?

No. It only reads results already reported in the header by a mail server.

Why are Received hops reversed?

Mail servers prepend Received headers, so reversing them shows the route in chronological order.

Can I upload an .eml file?

You can drop a text .eml file; the browser reads it locally and the analyzer extracts header-like fields.

Can forged headers mislead the analyzer?

Yes. The tool shows what the pasted header says. Some fields can be forged, so compare Received hops and authentication results from trusted mail servers.