What version of HTML to use in emails?

Question

What version of html would yo recommend for mail content to get best mail-client compatibility?

HTML 3.2
HTML 4.01 transitional
HTML 4.01 strict
XHTML 1.0

Answer 1

Keep it as legacy and forgiving as possible. That being said, most email clients will strip the head and html anyway so your doctype isn't really all that important.

Check out this great article: http://24ways.org/2009/rock-solid-html-emails and also this list of CSS properties and which email clients support them: http://www.campaignmonitor.com/css/