Read Time: 6 min

Here’s What We Learned After Tracking 17 Billion Email Opens [Infographic]


We’ve got an update!
Make sure to check out the most recent version of the Email Client Market Share infographic. You can find it here.

Over the course of the past year, we’ve analyzed over 17 billion email opens to see where subscribers read emails. And while a few things stayed the same, we saw plenty of movement this year in terms of email client popularity. In our 2016 Email Market Share infographic, we take a look at mobile, webmail, and desktop opens over the course of the year, providing insights about why these changes occurred and how they may affect your email campaigns.

To get a full, in-depth picture of all of the major innovations from the past year, read the 2017 State of Email Report.

Check out the infographic here, or read the transcription below it.


Tweet this infographic →

Which email clients are most popular with your audience?

While general email client open data is great for looking at trends, it’s your audience that matters. With the addition of a small tracking code to your campaigns, Litmus Email Analytics generates a report of where your subscribers open your emails. Use that data to focus your testing efforts—and ensure your campaigns look great in inboxes where your subscribers are opening.

Discover your audience →

2016 Email Client Market Share: Transcript

We tracked over 17 billion email opens in 2016 to determine where subscribers are reading emails. Here’s what we found…


The top 10 most popular email clients of 2016

  1. iPhone, 33%
  2. Gmail, 20%
  3. iPad, 13%
  4. Android, 9%
  5. Apple Mail, 7%
  6. Outlook, 6%
  7., 5%
  8. Yahoo! Mail, 2%
  9. Windows Mail, 1%
  10. Windows Live Mail, 1%


While mobile remained dominant, this year did see some oscillations for mobile, webmail, and desktop.


The “year of mobile” has come and gone—we’re now in a mobile era, with mobile representing 54% of all email opens.

Mobile stayed relatively steady throughout 2016, oscillating a couple of percentage points at most. However, market share did shift among the top mobile email clients:

  • iPhone: Increased to 33%
  • iPad: Increased to 13%
  • Android: Decreased to 9%

iOS represents 46% of total market share, which is great news for email developers since HTML and CSS are well-supported.


Webmail increased overall this year, growing from 27% to 30% of all email opens. This growth was largely driven by increased activity from Gmail.

  • Gmail: Increased to 20%
  • Yahoo! Mail: Decreased to 2%
  • Increased to 5%
  • Windows Live Mail: Increased to 1%

Mobile has dominated market share for several years now, but the drop in desktop (and subsequent rise in webmail) appears to be driven largely by growth in Gmail opens. This may be the result of larger companies moving to cloud-based solutions, rather than upgrading older versions of Outlook.


Desktop opens decreased overall in 2016, ending the year at 16%.

  • Apple Mail: Held at 7%
  • Outlook: Dropped to 6%
  • Windows Mail: Increased to 1%

Though Outlook’s popularity continues to decline, it can cause some headaches for email marketers depending on what version your subscribers are using. Outlook 2010 remains the most popular of the Outlook versions at 30% of all Outlook opens, while Outlook 2013 takes 24% of all opens. Outlook 2016 for Windows, released in September 2015, makes up 21% of all Outlook opens.

Outlook is a notorious offender for rendering quirks, but we’re teaming up with Microsoft to help them prioritize rendering issues faster. If you’d like to report an Outlook bug, shoot us an email:


Month-by-month highlights and email client news from 2016


Mobile began the year with 54% of all email opens, while webmail began the year at 27% and desktop at 19%.


Mobile opens climb back to 55%. Webmail opens decrease from 27% to 26% of opens, and desktop opens remain the same.

Microsoft finished rolling out its replacement of rendering engine with the infrastructure of Outlook 365.


Mobile, webmail, and desktop hold their positions at 55%, 26%, and 19%, respectively.


Mobile opens rose to 56%, representing a peak for mobile market share and the longest sustained growth after the holiday season, which tends to give momentum to mobile growth. Windows Mail knocks Thunderbird out of the top 10 email clients.

Gmail introduces the concept of glanceable newsletters in their Inbox by Gmail application.


Desktop opens increased to 20%, corresponding with a jump in Outlook opens. Webmail opens increased to 26%, and mobile opens dropped for the first time since January, to 54%. Windows Mail and Windows Live Mail trade the #9 and #10 spots this month.


Lots of webmail movement! Gmail increases to 16% and jumps up to 4%—the highest since May 2015. trades places with Yahoo! Mail, moving up to #7 on the top 10 list.


Mobile opens jumped back up to 56%, desktop opens decreased to 17%, and webmail opens held at 27%. Android increased to 10% total market share.


In August, mobile opens dropped back down to 55%, desktop opens decreased to 18%, and webmail opens increased to 28%.

Gmail now supports display: none, a CSS property that can hide specific elements of your email.


September rocked the email world! Gmail rolled out support for responsive design, improved font styling, and CSS for accessibility. Apple released iOS 10 and the iPhone 7.

Windows Mail officially overtook Windows Live Mail for the #9 spot, likely the result of Microsoft retiring Windows Live Mail.


While the overall percentage stayed the same for mobile, webmail, and desktop, Android dropped to 9.2% this month.


In November, webmail market share grew to 29%, while mobile and desktop dropped to 55% and 16%, respectively. Gmail remains the most popular webmail client by far, jumping up from 15% to 17% this month.


Mobile opens began and ended the year at 54% of all email opens. Webmail grew to 30%, driven by a jump from Gmail, now at 20% of all opens. Desktop decreased to 16%.

*Our 2016 market share data is derived from over 17 billion opens collected worldwide with Litmus Email Analytics between January 1, 2016 and December 31, 2016. It highlights worldwide trends across all industries and verticals. Some email clients may be over- or under- represented due to image blocking.

Make email better with the State of Email 2017 report

Want even more information and actionable takeaways? Get up-to-date on the latest email updates and advances by downloading the free report today.

Get the 2017 State of Email Report →

It’s time to get more from your marketing

Whether your team consists of one or 100, Litmus solutions are built to scale with you.

See Plans and Pricing