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Specifically, these clients do not support web fonts:

• All major webmail email clients such as Gmail, Yahoo! Mail and Outlook.com.
• The various incarnations of the Gmail mobile apps.
• The Outlook 2007/10/13/16 desktop clients.

The following email clients do support web fonts:

• Outlook 2000
• iOS Mail
• Apple Mail
• Android (default client, not Gmail)
• Thunderbird

As long as the email client supports the use of <link> there’s a pretty good chance web fonts will show up just fine.

Finding Web Fonts

To use web fonts you can either host the file yourself or use a web font hosting service, like Google Fonts. Google Fonts has a slick interface to select your custom fonts and build the necessary stylesheet. 

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