How to view the HTML source of an email

Updated 2026-11-10T00:00:00.000Z

Quick answer
In Gmail, open the email, click the three dots and choose Show original. In Apple Mail, choose View › Message › Raw Source. In Outlook on the web, open the message, click the three dots, then View › View message source.

Try it now

Every email is a text file with headers at the top and the message below, often in both plain text and HTML. Mail apps can show you that original file.

Gmail

1. Open the email.
2. Click the three dots ⋮ next to Reply.
3. Choose Show original. A new tab shows the headers and the full source.
4. Use Download original to save it as a file.

Outlook

• Outlook on the web and the new Outlook: open the message, click the three dots …, then View › View message source.
• Classic Outlook for Windows: open the message in its own window, right-click the message body and choose View Source to see the HTML. The headers are under File › Properties.

Apple Mail

Select the message and choose View › Message › Raw Source, or press Option+Command+U.

Yahoo Mail

Open the email, click the three dots … and choose View raw message.

Thunderbird

Select the message and choose View › Message Source, or press Ctrl+U (Command+U on a Mac).

Reading what you see

The headers come first: From, To, Subject, Date, and lines starting with Received that show which servers handled the message. The HTML part starts after a line with Content-Type: text/html. It may look scrambled if it is encoded; Gmail and Apple Mail decode most of it for you.

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