Email Header Analyzer

About this tool

Where do I find raw email headers?

In Gmail: open the email, click the three-dot menu, select 'Show original'. In Outlook: open the email, go to File > Properties, look in the Internet headers box. In Apple Mail: View > Message > All Headers.

What do authentication results mean?

The Authentication-Results header is added by the receiving server and summarizes SPF, DKIM, and DMARC results. 'pass' means authentication succeeded. 'fail' or 'softfail' means the check failed — often indicating spam or a misconfigured sending setup.

How are routing hops calculated?

Each Received header represents one hop — a server that handled the message. The delay between hops is calculated from the timestamps in each header. Large delays can indicate a slow relay, a spam filter hold, or clock skew.

What are X-headers?

Custom headers added by mail servers, spam filters, or sending platforms. They often contain metadata like spam scores, campaign IDs, or processing notes. They are informational and not part of the email standard.