What exactly is email client market share and why is it important?
There are countless applications and platforms your subscribers are using to view and engage with your emails. It wouldn’t be out of the realm of possibility to say there are hundreds of applications.
Litmus has reported on email client market share over the years to help email marketers everywhere understand monthly market trends for email clients like Gmail, Apple Mail, Outlook, and more. Knowing these movements empowers marketers to make better decisions when it comes to strategy and prioritization for design, coding, and overall email program focus.
May 2025 Email Client Market Share Report
Calculated from over 1.3 billion opens in Litmus Email Analytics, in May 2025.
Understanding email clients can be a nuanced affair—but it doesn’t need to be. Below, you’ll get a quick overview of what each email client in the top 10 actually refers to, including whether it’s a grouping of several email clients or specific to a platform or operating system.
Apple Mail, Apple iPhone, Apple iPad, and Apple’s Mail Privacy. Starting with Apple iOS 15 (iPhone), iPad OS 15, and Mac OS Monterey, opens from users opted into Apple’s Mail Privacy Protection do not pass along specifics of the email client version and platform. As such, they are not considered reliable opens, but we are able to determine if they are in Light or Dark Mode. Additionally, some third-party apps used on Apple devices will also show up as Apple.
Gmail in a web browser, Gmail mobile app (Android), Gmail mobile app (iOS), all reported as via Gmail’s image cache. Because of Gmail image caching, we do not get specifics of the Gmail email client version and platform. Email opens show as Gmail only if the email was opened in a Gmail client. If it’s sent to a gmail.com email address, but opened in an email client that is not a Gmail email client, it will show as the email client it was opened in. Learn more.
These are desktop opens in Outlook. The majority of these opens are Outlook 2016 and newer, which all have the same identifiers so we are not able to distinguish between them. Other opens include Outlook 2016 Pro, Outlook 2013, Outlook 2010, Outlook 2007, Outlook 2000-2003, and Outlook for macOS.
Similar to Gmail, Yahoo utilizes image caching to load images, which means we don’t get any specific information on the device. Opens reported as Yahoo Mail include webmail opens as well as mobile app opens on Android and iOS.
Opens in a mail app on an Android (does not include the apps that use image caching, such as Gmail and Yahoo). Learn more about how third party apps on mobile are identified.
Detection for QQ Mail was added on June 2022.
Users who log in to their Outlook webmail on a web browser. The web browser may be on desktop or mobile (For example, when someone opens a browser on their phone and goes to Microsoft to check their Outlook mail.)
All opens on the Mozilla Thunderbird email client, which is a free desktop client.
Detection for Orange.fr was added on June 2022.
All opens in the Samsung Mail app on Android.
How do we know which email client was used to open the email?
Email clients pass along a user agent string that helps identify them. Sometimes the same user agent is used for multiple email clients, or an app may use the user agent of the operating system/device it is being run on. That’s why it can get a little tricky to distinguish email clients! Using the email client market share as a guide for top 10 email clients is helpful, but it is not the only thing you should use to determine which email clients you should test against. Making sure your email looks great in a broad range of email clients is our top tip.
Get insights into your own email client market share
Your own top ten email clients may look different from this list. The best way to know is to track your own audience email client habits is using Litmus Email Analytics.
Get the kind of visibility into your audience your email service provider (ESP) alone can’t offer—including opens impacted by privacy measures introduced by email clients and Dark Mode usage. Try Litmus free for 7 days to get the data you need to be a more effective email marketer.
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Have a question about the State of Email Client Market Share not answered here?
Ask the communityWhat is the State of Email Client Market Share?
The State of Email Client Market Share is a leaderboard of the most popular email clients as collected worldwide by Litmus Email Analytics. The figures displayed in the chart are the top 10 most popular email clients, updated on a monthly basis.
How often are new email client market share reports published?
Every month, you’ll find a host of fresh email client market share data from Litmus Email Analytics, offering insights into email client usage from the previous month. We aim to update this page as early in the month as possible.
Where does the data for the State of Email Client Market Share come from?
The data represented in the email client market share is collected by real-life Litmus customers who are using Litmus Email Analytics in their own emails. All opens detected are completely anonymous and do not contain any Personal Identifiable Information (PII).
Does the State of Email Client Market Share include privacy-impacted opens?
The State of Email Client Market Share is powered by data collected globally by Litmus Email Analytics. With the introduction of Apple’s Mail Privacy Protection (MPP), any email opens detected in Apple Mail on iOS 15 or later are classified as privacy-impacted opens. Privacy-impacted opens are included in Apple Mail opens. Learn more about how Litmus Email Analytics reports on Apple Mail opens.
What are privacy-impacted opens?
Since Apple’s Mail Privacy Protection went into effect in September 2021, Apple Mail users are able to turn on a feature that will disable open tracking. Essentially, if an Apple Mail user has Mail Privacy Protection turned on, you will not know if that user opened your email or not.
What can I do with this data?
Staying on top of the email client movers and shakers will help you make better decisions for your email program. By tracking email client market share trends, you’ll be able to better predict changes that could happen to your own email client market share—and so prepare you for those changes. Think of the data on this page as a baseline for knowing which popular email clients your own audience is likely to use. And then use this information to start testing. Be sure to start tracking which email clients your own audience is using so you can hone in even more on your testing and personalization.
How do I see which email clients my audience is using?
Use Litmus Email Analytics to generate your very own email client market share and see which email clients your audience is using. All it takes is embedding a snippet of HTML code to your emails. After you send, that little snippet of code will report back to Litmus where every single email open is taking place. Plus, you’ll also see how long your audience is spending reading your email and if they’re using Dark Mode or not.
Email client market share
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