Free Email Header Analyzer
Paste raw email headers and see the full routing chain, authentication results, and delivery delays in a readable format.
How it works
Copy the raw email headers
In Gmail: open email > three dots > "Show original." In Outlook: open email > File > Properties.
Paste them into the analyzer
We parse every hop, timestamp, authentication result, and routing decision.
See the full delivery chain
Trace the email path from sender to recipient with timing, SPF/DKIM results, and delay analysis.
Why this matters
Email headers contain the complete story of how an email was delivered. When emails land in spam or get delayed, the headers tell you exactly why. Authentication failures, routing issues, and suspicious relay hops are all visible in the raw headers if you know where to look.
Monitor deliverability in real time
SendKit tracks authentication results and delivery routing across all your mailboxes. No headers to read manually.
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Got questions? We've got answers.
In Gmail: open the email, click the three dots menu, and select "Show original." In Outlook: open the email, go to File > Properties, and look for "Internet headers." Copy the full header block.
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