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Email Header Analyzer
Paste raw email headers to see SPF, DKIM, DMARC results, the Received hop chain, DKIM signatures, and ARC.
Analyze email headers
What is an email header?
Email headers are the metadata at the top of every message. They record who sent it, who relayed it, which authentication checks passed, and how long each hop took. RFC 5322 defines the format; RFC 8601 defines the Authentication-Results header that records SPF, DKIM, and DMARC verdicts.
What this header analyzer extracts
- From, Return-Path, Reply-To, Subject, Date, Message-ID
- Authentication-Results entries (SPF, DKIM, DMARC, ARC)
- All DKIM-Signature blocks with d= (signing domain), s= (selector), a= (algorithm)
- ARC-Authentication-Results chain for forwarded mail
- Received hops in chronological order with per-hop time deltas
- Composite verdict and findings list
How to copy headers from popular clients
| Client | Where to find headers |
|---|---|
| Gmail (web) | Open message → three-dot menu → Show original → copy all |
| Outlook (desktop) | Open message → File → Properties → Internet headers |
| Outlook.com / Microsoft 365 (web) | Open message → … → View → View message source |
| Apple Mail | Open message → View → Message → All Headers (or Raw Source) |
| Yahoo Mail | Open message → More → View raw message |
Frequently asked questions
Related free tools
References
Go beyond one-off checks
Safer Sender continuously monitors your domain's DMARC, SPF and DKIM, classifies every sender, and guides you safely from p=none to p=reject.