Email Header Analyzer
Paste the raw headers of an email to see its route, the delay at each hop, and how it did on SPF, DKIM and DMARC.
Free, no account needed.
What this analysis shows
- Every server the message passed through, in order, with the delay between hops.
- The SPF, DKIM and DMARC results recorded by the receiving server.
- The DKIM signing domain and selector, and whether the From, Return-Path and signing domains line up for DMARC.
- Warnings such as long delays, missing authentication, or mismatched sender domains.
How to get the headers
- Gmail: open the message, click the three dots, then Show original.
- Outlook on the web: open the message, click the three dots, then View → View message source.
- Outlook for Windows: open the message, then File → Properties and copy "Internet headers".
- Apple Mail: select the message, then View → Message → All Headers.
Frequently asked questions
Is it safe to paste headers?
Headers contain addresses and server names, not the message body. We analyze them to show you the result and don't keep them unless you have an Enterprise account with history turned on.
Why does a message show a long delay?
Usually the receiving server deferred it, for example because of greylisting or a busy server. The hop where the delay starts shows which system held it.
Related tools
- Email Deliverability TestSend one email to a unique test address and get a report on how it authenticates, exactly as a receiving server sees it.
- DKIM Record CheckerLook up a DKIM public key and check its type, length and syntax. Don't know the selector? Leave it blank and we'll try the common ones.
- SPF Record CheckerValidate a domain's SPF record, expand every include and see how close it is to the 10-DNS-lookup limit.
- DMARC CheckerLook up a domain's DMARC record and see exactly what it does: the policy, where reports go, and what to fix.