Email header analyzer

Paste an email's source (or just its headers) and get the three things people actually open headers for: the SPF / DKIM / DMARC verdicts, the delivery path as a readable hop timeline, and a full header table — plus automatic warnings when From, Return-Path and Reply-To domains disagree, a classic phishing tell.

Email source — full message or headers only

Analyze headers Load a sample Clear

Runs entirely in your browser — nothing is uploaded, and the message body is never parsed.

How to read the results

• SPF / DKIM / DMARC badges come from the Authentication-Results header added by the receiving server. pass is good, fail on SPF or DMARC in a message claiming to be your bank is game over.
• The hop timeline reverses the Received headers into chronological order — first the sending app's relay, last your inbox's MX. Timestamp gaps between hops show where mail queued.
• The header table keeps the original order, including repeated headers, so nothing is hidden.

Testing your own app's mail? Generate a real message to inspect: send one to a disposable Tempx inbox, open its source, paste it here.