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Does CSS text-transform Work in HTML Email?

Each of the six `text-transform` values defined by MDN (`capitalize`, `uppercase`, `lowercase`, `none`, `full-width`, `full-size-kana`).

Quick Answer

Does text-transform work in HTML email?

The CSS text-transform property is supported in all major email clients tested. You can use it with confidence in your HTML emails.

Which Email Clients Support CSS text-transform?

CSS support for text-transform across email clients

Email ClientDesktopMobile / WebNotes
Gmail✓ Yes✓ Yes
Outlook (Windows)~ Partial?
Outlook (Mac / Web)✓ Yes✓ Yes
Apple Mail✓ Yes✓ Yes
Yahoo! Mail✓ Yes✓ Yes
Samsung Email?✓ Yes
Thunderbird✓ Yes?
ProtonMail✓ Yes✓ Yes
Fastmail✓ Yes?

Notes

  • #1 Partial. `lowercase` value is not supported.

Currently, only Firefox supports the `full-width` and `full-size-kana` property values. Web clients on Firefox will support these properties.

Frequently Asked Questions

Related CSS Properties

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