Email Header Analyzer
Paste the raw headers from an email to break them apart. The analyzer unfolds wrapped lines, lists every header, pulls out From, To, Subject and Date, counts the Received relay hops, and reads the SPF, DKIM and DMARC results from Authentication-Results.
How to analyze email headers
- Open the original or raw source of the email and copy the header block.
- Paste it into the box; everything before the first blank line is parsed.
- Review the parsed fields, the hop count and the SPF, DKIM and DMARC results.
Examples
Authentication results
Authentication-Results: mx.test; spf=pass dkim=pass dmarc=fail
spf: pass, dkim: pass, dmarc: fail
Counting relays
Received: from a ... Received: from b ...
receivedHops: 2
Frequently asked questions
Where do I find the raw headers of an email?
Most clients have a Show original, View source or Show raw message option. Gmail calls it Show original, Outlook calls it View message source. Copy everything from the top down to the first blank line and paste it here.
What does the Received hop count tell me?
Each mail server that handles a message adds its own Received header, so the count is roughly the number of relays the email passed through. The headers are listed newest first, so the last Received line is usually the original sending server.
What are folded header lines?
Long headers may wrap onto following lines that begin with a space or tab, a practice called folding. The analyzer unfolds them back into a single value so a wrapped Subject or Received line reads as one piece of text.
What do the SPF, DKIM and DMARC results mean?
They are email authentication checks recorded in the Authentication-Results header. SPF verifies the sending server, DKIM verifies a cryptographic signature, and DMARC ties them to the From domain. A result of pass is good; fail or none can indicate spoofing or misconfiguration.
Are the headers I paste uploaded anywhere?
No. Parsing runs entirely in your browser, so the headers and any addresses in them never leave your device.
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