Responsive Web Design, Part 2 (2015)

Responsive Email Design

The Question Of Market Share

Whether you’re developing emails for yourself or someone else, knowing the distribution of these email clients across the list you’re sending to is an invaluable bit of information that can allow you to fine-tune your code to offer better experiences for readers.

Many ESPs will provide that data for you, but if you’re in a corporate or agency setting, you may not have access. If you can’t currently get that sort of data, you should fight tooth and nail for it, because developing without the knowledge of whether or not you have to support a particularly bad client is a massive handicap.

If you still don’t have access, you can find more generalized market share numbers on the web, though it might take a little bit of hunting. Litmus, helpfully, has done some of the footwork here.

Although emailclientmarketshare.com is a mouthful for a URL, it’s a wonderfully helpful page.

Though its numbers are calculated from a relatively small portion of email opens, the snapshot of market share that Litmus presents is accurate, and they end up being fairly similar to the top ten clients used by subscribers across the lists of MailChimp’s entire user base:

The top ten clients used by subscribers across MailChimp’s entire user base.

In the end, all the work of knowing what CSS is supported where, and which clients are the most popular in the world, or a particular country, or on an email list, is foundational. It’s not the end point of great email design and development, it’s where you start.

Armed with the knowledge of what can and can’t be done in email because of the constraints put in place by email clients, it should be plain to see that designing for email isn’t exceptionally different from designing for the web — there are simply more limitations to work around.