Email Header Analyzer
Paste an email header to inspect From, To, Subject, Received hops, Authentication-Results, SPF, DKIM, DMARC, ARC, and other common fields locally.
Summary
Paste a message header to analyze it.
Received route
N/A
Reported authentication
N/A
SPF, DKIM, DMARC, and ARC values shown here are reported by headers. ProntoUso does not revalidate them.
How to analyze email headers
Paste a raw email header to organize common fields, Received hops, and authentication results reported by mail servers.
Received route
Received headers are usually added at the top as a message moves between servers. The analyzer reverses them into an easier chronological route from earliest to latest hop.
Authentication results
SPF, DKIM, DMARC, and ARC values are read from headers such as Authentication-Results and Received-SPF. The tool reports what those headers say; it does not re-run DNS or cryptographic validation.
Common uses
- Review delivery paths during support troubleshooting.
- Find Message-ID, Return-Path, or Reply-To quickly.
- Read authentication results without digging through folded headers.
Processing notes
Headers are parsed locally in your browser and are never stored or uploaded.
FAQ
Does this validate SPF, DKIM, or DMARC?
No. It only reads results already reported in the header by a mail server.
Why are Received hops reversed?
Mail servers prepend Received headers, so reversing them shows the route in chronological order.
Can I upload an .eml file?
You can drop a text .eml file; the browser reads it locally and the analyzer extracts header-like fields.