A Guide to Viewing Full Email Headers in Gmail

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Email messages contain much essential information in their header area: the sender, recipients, subject, and tracking information. The latter data points can be used to troubleshoot email problems, for example, or to trace the odd unwelcome message back to its likely origin.

See Full Email Headers in Gmail

To get a message's full email headers displayed in Gmail:

  1. Open the email message in Gmail.
  2. Click the More downward-pointed arrowhead () next to the Reply button in the top right corner for the message whose headers you want to see.
  3. Select Show original from the menu that comes up.

See Full Email Headers for a Message in Gmail Basic HTML

To open a message's full view—including all email header lines—in Gmail's Basic HTML view:

  1. Open the message or conversation in Gmail Basic HTML.
  2. Make sure the individual email whose headers you want to see is expanded. ​Click the sender's name for the message or click Expand all if the message is not yet visible.
  3. Click Show original in the message's heading area, just above the email's content area.

The full message source will open in a new browser window or tab with the header lines on top; everything before the first empty line from the top is part of the message header.

Email Header Content

Email headers contain a significant amount of information—like digital postmarks—that identify how the message got from the sender to the recipient. If you report inappropriate messages to the authorities, you'll need to paste the full header content. It's not unusual for some header blocks to run more than 100 lines long and be filled with gibberish-looking strings.