Email Header Analyzer
When a specific email lands in spam and you need to know exactly why, the headers are the evidence. Paste your raw email headers to trace the message route, check authentication, and see where delivery failed.
From
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To
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Subject
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Date
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Authentication Results
Additional Details
Message Route
All Headers
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Understanding Email Headers
What are email headers?
Email headers are metadata attached to every email containing routing information, authentication results, timestamps, and server details. They're like a postal tracking slip showing every server that handled your email.
What do the authentication results mean?
SPF verifies the sending server is authorized. DKIM verifies the message wasn't altered in transit. DMARC aligns SPF and DKIM with the visible From address. All three passing means maximum trust.
Why are there delays between hops?
Each Received header represents a server that processed the email. Delays can indicate spam filtering, greylisting, server load, or network issues. Large delays (>30 seconds) may affect time-sensitive emails.
What is the Return-Path?
The Return-Path (also called envelope sender or bounce address) is where bounce notifications are sent. It's different from the visible From address and is used in SPF evaluation.
Related Free Tools
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