FernTool

How to view full email headers

Email headers are the hidden lines at the top of every email that show who really sent it, which servers it passed through and whether it passed the anti-fake checks (SPF, DKIM and DMARC). You need them to check a suspicious email, or when IT support asks “can you send me the headers?”. Here’s where to find them in each email app. Once copied, paste them into the email header analyzer for a plain-English answer.

Gmail (computer)

  1. Open the email.
  2. Click the three dots (⋮) next to the Reply arrow, top right of the message.
  3. Choose Show original. A new tab opens with a summary (SPF, DKIM, DMARC) and the full headers.
  4. Click Copy to clipboard.

The Gmail app on Android and iPhone can’t show headers. Open Gmail in a browser on a computer, or forward the email to yourself and check it later on a computer.

Outlook on the web, Outlook.com and the new Outlook for Windows

  1. Open the email.
  2. Click the three dots (More actions) at the top of the message.
  3. Choose View → View message details.
  4. Select everything in the box (Ctrl+A) and copy it (Ctrl+C).

Classic Outlook for Windows (Microsoft 365, 2016–2024)

  1. Double-click the email so it opens in its own window.
  2. Click File → Properties.
  3. The headers are in the Internet headers box at the bottom. Click inside it, press Ctrl+A, then Ctrl+C.

Apple Mail (Mac)

  1. Select the email.
  2. Choose View → Message → All Headers (Shift+Command+H) to show them above the message, or View → Message → Raw Source (Option+Command+U) to see the full source.
  3. Copy the header lines (everything above the first blank line).

Yahoo Mail

  1. Open the email.
  2. Click the three dots (More) in the toolbar.
  3. Choose View raw message and copy the text that opens.

iPhone, iPad and Android mail apps

Most phone apps don’t show full headers. The easiest route: on a computer, sign in to the same mailbox in a browser (Gmail, Outlook.com, Yahoo or your company webmail) and follow the steps above. Forwarding the email to someone else doesn’t keep the original headers, so if IT asks for them, send the email “as an attachment” (Outlook: More actions → Forward as attachment; Gmail: tick it, then ⋮ → Forward as attachment).

What to look for once you have them

The email header analyzer reads all of this for you, shows the route and the sending server on a map, and gives a one-line verdict. Nothing you paste is stored.

Frequently asked questions

Is it safe to share my email headers?

Mostly yes: headers don’t contain your password or the email’s text. They do show your email address, the sender’s address, the subject and the servers involved, so only share them with people you trust, like your IT support. FernTool’s analyzer doesn’t store what you paste.

Why can’t I see headers in the Gmail app?

Google only offers “Show original” in Gmail on the web. Open gmail.com in a browser on a computer (or in desktop mode on your phone’s browser) to get it.

What is the difference between headers and the message source?

The headers are the technical lines at the top. The message source (or “original”, or “raw message”) is the whole email: headers, then a blank line, then the body and attachments. For checking who sent an email, the headers are all you need.

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