PowerMTA.in resource
Free Email Header Analyzer
Paste the raw headers from an email. The analysis happens in your browser; the page does not need to upload the header to a server.
What it can identify
- Authentication-Results lines
- SPF, DKIM and DMARC status when present in the header
- ARC status when present
- From, Return-Path and Message-ID fields
- Received header chain
A header analyzer is a diagnostic aid, not a guarantee of inbox placement or sender reputation.
How to read an email header
An email header records the technical path and authentication results associated with a message. When troubleshooting delivery, start with the Authentication-Results field, then review the Received chain, Message-ID, Return-Path, and DKIM signing information. A header can reveal whether SPF, DKIM, and DMARC passed and whether the visible From domain aligned with the authenticated domains.
What to look for
- SPF: confirms whether the sending IP was authorized for the envelope sender domain.
- DKIM: confirms whether a cryptographic signature validated for the signing domain.
- DMARC: evaluates authentication and alignment for the visible From domain.
- Received: shows the sequence of mail servers that handled the message.
- ARC: can preserve authentication context when messages pass through intermediaries.
Privacy note: analyze headers locally where possible and remove recipient addresses or other sensitive information before sharing a header with a third party.