Free tool
Email header analyzer
Paste the headers of an email to see the path it took and how long each hop waited, whether SPF, DKIM and DMARC passed, who signed it, and whether those domains line up with From. Nothing leaves your browser.
What the analyzer reads
- Received: every server adds one on top, so reading them bottom to top gives the path. The time at the end of each shows where the email waited.
- Authentication-Results: the receiving server's SPF, DKIM and DMARC verdicts.
- DKIM-Signature: who signed the email (
d=) and with which key (s=). Check that key with the DNS checker. - From and Return-Path: the two domains DMARC compares against the signature and SPF.
Questions
- Where do I find an email's headers?
- In Gmail, open the email, then the three-dot menu and Show original. In Outlook on the web, the three-dot menu, then View and View message source. In Apple Mail, View → Message → All Headers. Copy everything down to the first blank line.
- Is it safe to paste headers here?
- The analysis runs in your browser; the text is not sent anywhere. Headers can still contain addresses and IPs, so treat a copy you share with others the way you would treat the email itself.
- What does alignment mean?
- DMARC passes only when SPF or DKIM passes for a domain that matches the From domain. A signature from your provider's own domain, or a bounce address on its domain, can pass on its own and still not count for DMARC.
- Why are some delays negative?
- Each server stamps the time from its own clock. A negative delay means one of them is off, not that mail travelled back in time.
Read the headers of every test email
Zyntra returns each email's full headers over the API and in the web viewer. Free plan, no setup.
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