How to Send a Responsive HTML Email from Outlook on the web and Gmail

  1. Open the email in a browser and copy it’s source code
  2. Inline the CSS using a tool such as
  3. In Outlook on the web or Gmail, create a new email message
  4. In the body of the email, type some text that can easily be found, e.g. a bunch of hash symbols.
  1. Inspect the text you just typed and in your inspector, edit it by replacing the text you typed with the CSS-inlined email source code.
  1. Your email body will now show the HTML email. Click send.