We regularly test these email clients using internal test tools and Email on Acid.
Fully supported
All the options work properly. Fallback fonts display where web fonts are not supported.
Desktop
Apple Mail 13, 14, 15 & 16
Microsoft Outlook for Windows 2007, 2010, 2013, 2016, 2019, 2021, Microsoft 365*
Microsoft Outlook for Windows, Microsoft 365 “New Outlook”*
Outlook for Mac (Microsoft 365)**
Outlook for Mac 16 (Legacy Outlook)
Web fonts are not supported.
** Web fonts are no longer supported since version 16.79.3 (December 2023)
Mobile
iOS Mail (iPhone & iPad)
Gmail App (iOS)*
Gmail App (Android 8, 9, 10, 11, 12 & 13)*
Outlook App (Android & iOS)*
Yahoo App (Android & iOS)*
Web fonts are not supported.
Web
Gmail
Google Workspace
Yahoo
AOL Mail
Comcast
Note: none of the above services supports web fonts
Partial support for some options
Messages display correctly, but some options (with low impact) may not display as expected.
Desktop
Microsoft Outlook for Windows on high-resolution displays *
Web fonts are not supported. Applies a font resize that may expand the layout.
Not yet supported
This list includes new and updated mobile email clients with compatibility issues.
Huawei Mail App (Android)
Only basic settings works
When sending to these clients, we recommend using text and images in a simple one-column layout.
Desktop
Thunderbird
Lotus Notes 7, 8 & 8.5
Windows 10 Mail
Windows 11 Mail
IBM Notes 9 & 10
Web
GMX.de
Web.de
freenet.de
Libero Mail
Mobile
Web clients (mobile browser versions)
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