Browsers/operating systems/platforms we use for testing in Previews
Litmus runs its tests on whichever platform is most appropriate for a particular client. There are some exceptions, due to licensing constraints, where Litmus may use a slightly older or newer version of an operating system to offer better, cheaper, and faster testing to our customers.
We share our currently available email client previews on our Litmus site.
Microsoft Windows
| Email Client | Version | Operating System |
|---|---|---|
| IBM Notes 9 | 9.0 | Windows 10 |
| IBM Notes 10 | 10.01 | Windows 10 |
| Lotus Notes 8.5 | 8.5.3 | Windows 10 |
| Outlook 2007 | 12.0.6770.5000 | Windows 10 |
| Outlook 2010 | 14.0.7177.5000 | Windows 10 |
| Outlook 2013 | Outlook 15.0.5353.1000 MSO 15.0.5363.1000 | Windows 10 |
| Outlook 2013 120 DPI | Outlook 15.0.5353.1000 MSO 15.0.5363.1000 | Windows 10 |
| Outlook 2016 | Outlook 16.0.5182.1000 MSO 16.0.5188.1000 | Windows 10 |
| Outlook 2016 120 DPI | Outlook 16.0.5182.1000 MSO 16.0.5188.1000 | Windows 10 |
| Outlook 2019 | Version 1808 (Build 16.0.10377.20023) | Windows 10 |
| Outlook 2019 120 DPI | Version 1808 (Build 16.0.10377.20023) | Windows 10 |
| Outlook 2021 | 16.0.14332.20102 | Windows 10 |
| Outlook 2021 120 DPI | 16.0.14332.20102 | Windows 10 |
| Outlook 2021 (Dark Mode) | 16.0.14332.20102 | Windows 10 |
| Outlook Office 365 | Version 2411 (Build 18227.20222) | Windows 10 |
| Outlook Office 365 120 DPI | Version 2411 (Build 18227.20222) | Windows 10 |
| Thunderbird | 60.6.1 | Windows 10 |
| Outlook for Windows | Version 1.2025.117.600 | Windows 11 |
| Outlook for Windows (Dark Mode) | Version 1.2025.117.600 | Windows 11 |
macOS
| Email Client | Version | Operating System |
|---|---|---|
| Apple Mail 16 | 16.0 | 13.5 (Ventura) |
| Apple Mail 16 (Dark Mode) | 16.0 | 13.5 (Ventura) |
| Outlook for Mac | 16.94 (25020927) | 15.3 (Sequoia) |
| Outlook for Mac (Dark Mode) | 16.94 (25020927) | 15.3 (Sequoia) |
Note: Apple Mail preview clients have Mail Privacy Protection (MPP) enabled. MPP does not impact Outlook clients on macOS.
Web-based email
Our web-based email client results are opened on Windows 10 machines using the following web browsers:
- Chrome 114
- Firefox 130
- Microsoft Edge 115
Our Outlook.com dark mode clients are configured using the dark theme on Outlook.com rather than Windows settings. Windows settings are in light mode.
iOS devices
The table below shows the mobile device and its operating system. We use the native mail application included for each mobile device.
| Mobile Device | Operating System |
|---|---|
| iPad (Gen 9) | iOS 18.2 |
| iPad (Gen 9 Dark Mode) | iOS 18.2 |
| iPad (Gen 10) | iOS 18.2 |
| iPad (Gen 10 Dark Mode) | iOS 18.2 |
| iPad Pro (11 and 12.9-inch) | iOS 18.2 |
| iPad Pro (11 and 12.9-inch) (Dark Mode) | iOS 18.2 |
| iPad Air (Gen 4) | iOS 18.2 |
| iPad Air (Gen 4) (Dark Mode) | iOS 18.2 |
| iPad mini (Gen 6) | iOS 18.2 |
| iPad mini (Gen 6) (Dark Mode) | iOS 18.2 |
| iPhone 13 | iOS 15.0 |
| iPhone 13 (Dark Mode) | iOS 15.0 |
| iPhone 13 Pro Max | iOS 15.0 |
| iPhone 13 Pro Max (Dark Mode) | iOS 15.0 |
| iPhone 14 | iOS 16.4 |
| iPhone 14 (Dark Mode) | iOS 16.4 |
| iPhone 14 Pro Max | iOS 16.4 |
| iPhone 14 Pro Max (Dark Mode) | iOS 16.4 |
| iPhone 15 | iOS 17.0 |
| iPhone 15 (Dark Mode) | iOS 17.0 |
| iPhone 15 Plus | iOS 17.0 |
| iPhone 15 Plus (Dark Mode) | iOS 17.0 |
| iPhone 16 | iOS 18.0 |
| iPhone 16 (Dark Mode) | iOS 18.0 |
| iPhone 16 Plus | iOS 18.0 |
| iPhone 16 Plus (Dark Mode) | iOS 18.0 |
| iPhone 16 Pro | iOS 18.0 |
| iPhone 16 Pro (Dark Mode) | iOS 18.0 |
| iPhone 16 Pro Max | iOS 18.0 |
| iPhone 16 Pro Max (Dark Mode) | iOS 18.0 |
Note: iPhone previews on devices using iOS 15 or later have Mail Privacy Protection (MPP) enabled.
iOS apps
The table below shows the app, mobile device, and operating system.
| App | Mobile Device | Operating System |
|---|---|---|
| Gmail App | iPhone 16 | iOS 18.2 |
| Gmail App Dark | iPhone 16 | iOS 18.2 |
| Microsoft Outlook App Version 4.2229.0 |
iPhone 16 | iOS 18.2 |
Android devices
We currently use Gmail accounts within the following clients:
| Email Client | Version | Device | Android Version |
|---|---|---|---|
| Gmail (Android 7) | 2020.09.06.332325283 | Google Pixel | Android 7.1.1 (Nougat) |
| Gmail (Android 8) | 2020.09.06.332325283 | Google Pixel 2 | Android 8 (Oreo) |
| Gmail (Android 9) | 2020.09.06.332325283 | Google Pixel 3 | Android 9 (Pie) |
| Gmail (Android 10) | 2020.09.06.332325283 | Google Pixel 4 | Android 10 |
| Gmail (Android 10 Dark) | 2020.09.06.332325283 | Google Pixel 4 | Android 10 |
| Gmail (Android 11) | 2020.09.06.332325283 | Google Pixel 5 | Android 11 |
| Gmail (Android 11 Dark) | 2020.09.06.332325283 | Google Pixel 5 | Android 11 |
Special Conditions
We currently use IMAP accounts within the following clients:
| Email Client | Version | Device | Android Version |
|---|---|---|---|
| Samsung Mail (Android 7) | 7.1.1 | Samsung Galaxy S8 | Android 7.1.1 (Nougat) |
We currently use Office365 accounts within the following clients:
| Email Client | Version | Device | Android Version |
|---|---|---|---|
| Microsoft Outlook | 4.2223.0 | Google Pixel 5 | Android 11.0 |
| Microsoft Outlook Dark | 4.2223.0 | Google Pixel 5 | Android 11.0 |
Microsoft Outlook
Outlook for Microsoft Windows uses the Microsoft Word rendering engine to render emails. The table below shows the different rendering engines for the different versions of Outlook Litmus has to offer. Read more about Outlook rendering in this blog post.
| Email Client | Version Used |
|---|---|
| Outlook 2007 | Word 2007 |
| Outlook 2010 | Word 2010 |
| Outlook 2013 | Word 2013 |
| Outlook 2016 | Word 2016 |
| Outlook for Mac | WebKit |
| Outlook 2019 | Word 2019 |
| Outlook 2021 | Word 2021 |
IBM Notes
Notes 8.5 selects its rendering engine from the operating system's installed version of Explorer. Litmus uses Internet Explorer 8 on any machine running Lotus Notes 8.5.
Screen resolution
We currently use 1366x768 resolution. PC-based desktop/webmail client and browser previews are on machines using 96 DPI unless noted.