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Does CSS clamp() Work in HTML Email?

Support for the CSS `clamp()` function.

Quick Answer

Does clamp() work in HTML email?

The CSS clamp() property is supported in Gmail, Apple Mail, Thunderbird, ProtonMail. It is NOT supported in Outlook (Windows), Outlook (Mac / Web), Yahoo! Mail, and others. Always include a safe fallback for unsupported clients.

Which Email Clients Support CSS clamp()?

CSS support for clamp() across email clients

Email ClientDesktopMobile / WebNotes
Gmail✓ Yes~ Partial—
Outlook (Windows)✗ No?—
Outlook (Mac / Web)✗ No✗ No—
Apple Mail✓ Yes✓ Yes—
Yahoo! Mail✗ No✗ No—
Samsung Email?✗ No—
Thunderbird✓ Yes?—
ProtonMail✓ Yes✓ Yes—
Fastmail✗ No?—

Notes

  • #1 Partial. Not supported with non Google accounts.

Frequently Asked Questions

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