Free Email Header Analyzer
Paste raw email headers to see who really sent a message, which servers it passed through, and whether SPF, DKIM and DMARC passed.
No external API — headers are parsed locally in your browser.
In Gmail: open the message → three-dot menu → Show original → copy everything.
Your analysis appears here
Paste headers and hit Analyze to see authentication results, the sending server and the full delivery path.
Headers are the only honest record of how an email reached you
The visible From line can be faked. The header block cannot be, and it tells you everything.
Spot spoofing and phishing
If the From address says your bank but SPF fails and the Return-Path points at an unrelated domain, the message is forged. Authentication results plus the sending IP settle the question in seconds.
Diagnose slow or missing mail
Each Received line records a server and a timestamp. Reading the hops in order shows exactly where a message sat — a greylisting relay, a slow gateway, or a filter that quarantined it before delivery.
How to use this analyzer
Open the message in Gmail, choose Show original, copy the header block, paste it above and click Analyze. You get the message details, SPF, DKIM and DMARC badges, the sending IP and every delivery hop in order.
Example usage: verifying your own sends
Send a test campaign to yourself, paste the received headers here, and confirm all three authentication checks pass. If DKIM is neutral, your signature is not being verified — fix the DNS record before your next big send.
Frequently asked questions
Everything people usually ask about this tool.
More free email tools
Small, focused utilities that help you write, check and send better email.
Score your full email for spam triggers before sending.
Score subject lines for length, clarity and open rate.
Build a clean, professional Gmail signature in seconds.
SPF Checker
Coming soonValidate the SPF record for your sending domain.
DKIM Checker
Coming soonConfirm your DKIM signature is published correctly.
DMARC Checker
Coming soonReview your DMARC policy and alignment.
Need to send personalized Gmail campaigns from Google Sheets?
Once your authentication is clean, the next step is sending mail people actually want. Mailvern sends personalized email straight from your own Gmail, only to the rows in your sheet that match your conditions.