Email header analyzer
Paste raw message headers to inspect authentication results, routing, and delivery delays.
Read the path behind a message
Email headers record how a message moved between servers and how receiving systems evaluated SPF, DKIM, and DMARC. This tool parses the pasted text locally in your browser.
- Trace Received headers in chronological order
- Inspect SPF, DKIM, and DMARC results
- Compare delay between mail servers
- Review sender and message metadata
Received
The path taken
Every server that touched the message adds a line, newest at the top.
Timing
Where it waited
Gaps between hops show which server held on to the message.
Results
How it was judged
The SPF, DKIM, and DMARC outcomes the receiving system recorded.
Origin
Where it started
The bottom line is the first sender, and the hardest part to forge.
Common questions
- Where do I find raw headers?
- In Gmail, open the message and choose Show original. In Outlook, use File then Properties.
- Which Received line is the real sender?
- The bottom one. Each server adds its own to the top, so the list runs newest to oldest.
- Can headers be faked?
- Lines added before your provider can be. The ones your own mail system wrote, including authentication results, cannot.
- What does a long gap between hops mean?
- A server queued the message, usually from greylisting, a retry, or a backlog.
- Is my pasted header sent anywhere?
- No. Parsing runs in your browser and nothing leaves the page.
Use these checks during signup
The API returns allow, review, or block with the reasons behind it.