Free Tool • 100% Client-Side

Email Header Analyzer

Paste raw email headers below. We'll show you authentication results, routing hops, and delivery details.

Your headers never leave your browser — all analysis is done locally.

How to View Email Headers

Gmail

Open the email, click the three dots (⋮) in the top right, select Show original. Copy all the headers from the top of the page.

Outlook / Microsoft 365

Open the email, click the three dots (⋮), select View message source or go to Message Properties and copy the Internet Headers.

Apple Mail

Open the email, go to View → Message → All Headers, or use View → Message → Raw Source.

ProtonMail

Open the email, click the three dots (⋮), select View headers.

What Are Email Headers?

Email headers are metadata attached to every email. They contain the complete routing path from sender to recipient, plus authentication results (SPF, DKIM, DMARC, ARC), timestamps, and server information.

Headers are added by each mail server that handles the message. The most recent headers appear at the top, and the oldest at the bottom — so you read them bottom-to-top to trace the delivery path.

Analyzing headers helps you diagnose delivery problems, identify spoofing attempts, measure server delays, and verify that authentication is passing correctly.

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