Want to know more about emails than Gmail shows you on the surface? Find out here how to view email headers in Gmail (on the desktop using a browser and on mobile devices, too).
First, Emperor Nero Looks at Something
More specifically, writes Pliny the Elder famously, he looks at gladiators not directly but through “smaragdi,” emeralds that are “generally concave in shape, so that they concentrate the vision.”
Did the emperor use an early version of glasses to amplify his vision? Probably not; chances are, neither did he look through a gemstone nor use it as a reflecting mirror. Possibly, Nero did not look at the gladiators at all…
Either way, the story is fascinating and well worth examining—as are email headers in Gmail, through smaragdi or liquid crystals:
How to View Basic Email Headers in Gmail
Gmail Web Interface and Apps for iPhone and Android
Time needed: 5 minutes
To examine key header lines for an email in Gmail using the desktop web interface or the Gmail app for iOS and Android:
- Open the message whose heads you want to view in the main Gmail window or in its own window.
- Click the Show details triangle next to the receiving email address.
- Find a selection of important header lines in formatted fashion.
What’s what: See below for a list of headers you can usually view in Gmail message details and their meaning.
- For viewing all header lines in Gmail, see below.
Email Headers in Gmail “Show Details” View Explained
| Header | Explanation |
|---|---|
from: | The message’s sender as set by the sender. This will always include an email address and optionally a name. Example: Heinz from La De Du <heinz@ladedu.com> |
reply‑to: | The email address that will receive replies if you click Reply in Gmail. This can but need not be different from the from: address. Example: Heinz at La De Du <replies@ladedu.com> |
to: | The email address (or addresses) listed as the primary recipient (or recipients). You may find your Gmail address here, for example, a Gmail alias, or a different recipient’s address (if you are a Cc: or Bcc: recipient, for instance). Example: me+Gmail-Tips@gmail.com |
date: | The date given in the message (not necessarily the date the email was sent on its way or delivered) converted to your Gmail time zone. Example: Aug 31, 2020, 12:39 PM |
subject: | The email’s subject line (which you will also see as the message’s title) Example: Sign Out in Gmail (Even Automatically) |
Gmail also displays information derived from the headers but not corresponding directly to specific email headers on the message details sheet:
| Pseudo‑Header | Explanation |
|---|---|
mailing list: | If the message was sent through a mailing list or newsletter, Gmail will show its best guess for the list’s email address (drawn from the To: or From: headers, or from List-ID:, for instance). Example: 9fce4fb8cd679ebdb26c82da7mc list <9fce4fb8cd679ebdb26c82da7.87109.list-id.mcsv.net> |
mailed‑by: | The originating SMTP email server. Example: gmail.com |
signed‑by: | The domain whose key was used to sign the message for authenticity. Usually, Gmail displays the DKIM signature. DKIM allows domain owners to specify email servers that are allowed to send messages with the domain name in the From: header line. Example: ladedu.com |
security: | A summary whether the message has been encrypted; the possible values are – Enhanced encryption S/MIME: the email has been encrypted with the recipient’s key, and only the recipient can decrypt and read the message – Standard encryption TLS: the message has been sent through an encrypted connection but has not itself been encrypted with a personal key – No encryption: the message was sent in plain text for anybody to intercept during delivery |
How to View All Email Headers in Gmail
On the Desktop
To view all header lines unaltered in Gmail using full web-based Gmail:
- Open the email whose header information you want to view.
- Click the More three-dots menu button next to the header.
Not the Gmail toolbar: Do not click the More three-dots menu button in the Gmail toolbar (above the reading pane).
Gmail conversation view: In Gmail conversation view, too, click next to the header information for the email whose headers you want to see. - Select Show original from the menu that has appeared.
- View the message headers in the window that opens:
– from the first line of the message source view (set in Courier or another proportional-width font)
– to the first empty line.
Here, you do get the full message source in Gmail, of course, including the full body, HTML source, MIME parts and attachments,
On a Mobile Device
The mobile version of Gmail on the web and the Gmail apps for Android and iOS do not provide direct access to viewing all email headers. You can work around this, however.
To view all email headers for an email in Gmail using a mobile device:
- Open full Gmail in a mobile browser such as Chrome or Safari.
Faster: Viewing headers in basic HTML Gmail may be the faster choice; see below. - Open the email and view full headers as above.
How to View Email Headers in Gmail: FAQ
Can I view email headers in basic HTML Gmail?
Yes.
To access all email headers in basic HTML Gmail:
- Open the message whose headers you want to view.
- Click or tap Show original underneath the message’s condensed headers.
- Find the full header information presented just like in full desktop Gmail.
(How to view email headers in Gmail tested on the web and the Gmail app for iOS; updated March 2024)