Free tool · Headers never leave your browser
What really happened
to that email?
Every email carries its own flight recorder. Paste the raw headers and read it: authentication verdicts, domain alignment, and every server hop with its delay.
Parsed entirely in your browser — headers contain private routing data, so nothing is uploaded and nothing is kept in the URL.
Three things headers reveal that dashboards don't
The receiver's verdict, verbatim
Authentication-Results is the receiving server speaking for itself. When a prospect says 'it went to spam', this header tells you whether authentication was the reason — or an alibi.
Alignment failures
SPF can pass and still count for nothing if it passed for your provider's domain instead of yours. The alignment check catches the gap between 'passing' and 'protecting'.
Where the time went
A 4-minute hop delay at the receiver is greylisting — normal for new senders. A 30-minute delay at your own relay is a queue problem. Same symptom ('it arrived late'), opposite fixes.
Questions, answered honestly
How do I get the raw headers of an email?
Gmail: open the message → three-dot menu → 'Show original' → copy everything. Outlook (desktop): File → Properties → 'Internet headers'. Outlook web: three-dot menu → View → View message source. Apple Mail: View → Message → All Headers. Paste the whole block here — the parser ignores the body if it tags along.
What do the SPF, DKIM and DMARC chips mean?
They're the receiving server's own verdicts, read from the Authentication-Results header. pass means that mechanism checked out; fail means it didn't; none means the sender never set it up; missing means the receiver didn't record a verdict. These are the three checks that decide trust before content is even considered.
What is alignment, and why does the tool check it separately?
DMARC requires that SPF or DKIM pass for the same domain shown in the From header — not just pass in general. Mail through a provider often passes SPF for the provider's bounce domain instead of yours; the DKIM signature might be the provider's too. Both are 'valid' yet do nothing for your DMARC. Alignment failures are the most misdiagnosed deliverability problem there is.
What does the delivery path tell me?
Every server an email crossed, oldest first, with the wait at each hop. Long delays usually mean greylisting (a receiver asking 'try again later'), a queue backlog at a relay, or a struggling server. The path also exposes the true origin — useful when something claims to be sent from somewhere it wasn't.
Are my headers uploaded to your servers?
No. Parsing happens entirely in your browser's memory. Headers reveal IPs, server names and routing details, so this tool deliberately stores nothing — not even in the URL.
Forensics are fun once. Automation is better.
Norbelys traces every email it sends automatically — sent, delivered, opened by a real human, replied — so you debug from a timeline, not from pasted headers.
Start sendingFrom $29/mo · Cancel anytime