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Does CSS rgb() Work in HTML Email?
RGB functional notation (`rgb()`)
Quick Answer
Does rgb() work in HTML email?
The CSS rgb() property is supported in all major email clients tested. You can use it with confidence in your HTML emails.
Which Email Clients Support CSS rgb()?
CSS support for rgb() across email clients
| Email Client | Desktop | Mobile / Web | Notes |
|---|---|---|---|
| Gmail | ~ Partial | ~ Partial | — |
| Outlook (Windows) | ~ Partial | ? | — |
| Outlook (Mac / Web) | ✓ Yes | ✓ Yes | — |
| Apple Mail | ✓ Yes | ✓ Yes | — |
| Yahoo! Mail | ~ Partial | ~ Partial | — |
| Samsung Email | ? | ✓ Yes | — |
| Thunderbird | ✓ Yes | ? | — |
| ProtonMail | ✓ Yes | ✓ Yes | — |
| Fastmail | ✓ Yes | ? | — |
Notes
- #1 Whitespace syntax is not supported (`rgb(0 128 0 / 1)`).
- #2 Alpha value is not supported (`rgb(0, 128, 0, 0.5)`).
- #3 whitespace syntax (`rgb(0 128 0)`): when used in the `style` attribute of an element, the whole attribute is stripped. When used inside `<style>`, the whole `<style>` block is stripped.
Frequently Asked Questions
Related CSS Properties
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