How Does Responsive HTML Work in Various Email Clients?

The ‘responsive’ word in the world of web browsers, means that the layout of the content will adjust to the width of the viewport, but it won’t happen automatically! Even if you code a superb responsive email template, with the appropriate CSS based media queries and CSS properties for different viewport sizes, your responsive email won’t change it’s layout in a lot of email clients. Why?

Because not all email clients support CSS media queries. Only modern web browsers do! The field of email works a bit differently, as usual.

Email clients regularly strip parts of the HTML for various security reasons. Also sometimes they remove CSS media queries too, or the viewport meta tag, which helps us to set the default behavior for different pixel densities and device widths.

And this is still not the whole picture! There are additional email client specific nuances, which tend to break up everything.

For example YahooMail does not support CSS media queries, but still allows all of the CSS properties that we include in the media query blocks. That can make a really big mess.

Here’s a summary of how the most popular email clients will handle our (and others’) responsive emails templates as well. We hope it helps clear the air!

Email client	Type	Media Query / Responsive	EDMdesigner generated HTML
Outlook 2007/2010/2013	desktop	not supported	desktop version
Outlook 97/03/Express/Mail	desktop	not supported	desktop version
Thunderbird 31	desktop	not supported	desktop version
Apple Mail 6.5+	desktop	supported	desktop/mobile version (based on window width)
iOS 7 – iPad	tablet	supported	desktop/mobile version (based on orientation and resolution)
iOS 7 – iPhone	mobile	supported	mobile version
Gmail App	mobile	not supported	desktop version without width values
Gmail.com	browser	not supported	desktop version
Outlook.com	browser	supported	desktop/mobile version (based on window width)
YahooMail	browser	not supported	desktop version

It’s easy to be responsive in web browsers, since they have the ability, to render (re-render) the HTML any time and they also support scripts (JavaScript, activeX, Flash, etc) which help us change look and feel easily. **Email clients regularly deny all kind of scripts** for security issues **and** in addition they **tend to render your HTML code only once** (when it shows up on your screen) and won’t change it if you resize your reader window for example.

Email client developers do not really care about rendering HTML on-the-fly. They focus on building a secure software and frankly this is the easiest way. But not the best one at all. Until the developers of various email clients stick to this old style method, we won’t be able to produce magically responsive email templates.

We “just” have to accept that responsive emails won’t be perfectly responsive in many email clients. It’s strange, we know. But that’s all folks!