Mail Header Analyzer

The Mail Header Analyzer takes the raw header block from an email you received — copied from your mail client's "show original", "view source", or message properties — and breaks it down field by field. It reports the SPF, DKIM and DMARC authentication results against their expected values, traces the Received chain hop by hop with the delay at each step, and flags sender-consistency issues. Everything is analyzed in your browser; the headers are never sent to our servers.

Why it matters

Email headers are where you confirm whether a message is genuinely from who it claims to be and how it actually reached you. Reading them by hand is tedious and easy to get wrong — a failed DKIM, a Reply-To pointing somewhere unexpected, or a suspicious hop is easy to miss. Analyzing each entry against its known/expected value turns a wall of text into a clear verdict, which is invaluable when investigating phishing, spoofing, or slow delivery.

Examples

Investigating a suspected phishing email: check whether SPF, DKIM and DMARC actually passed and whether Reply-To quietly differs from the From domain.
Diagnosing slow delivery: read the Received chain to see which hop introduced the delay.
In Gmail use "Show original", in Outlook open Message Options / "View source", then paste the whole header block here.