CSS property · data last changed 10 Nov 2026
backdrop-filter in email clients
Works in 6 of 21. Not supported in Gmail, Gmail Android, Gmail iOS and 9 more. Untested in Thunderbird, HEY Mail and Fastmail.
Your reader in Outlook Classic sees the email without backdrop-filter, even if it looks right where you tested it.
caniemail (MIT) via @emailens/engine 0.18.22
What to do instead in Outlook Classic
Treat backdrop-filter as decoration only. Provide a sensible solid or semi-transparent background-color so non-supporting clients render a coherent visual. Do not rely on the blur effect for legibility separation.
There is no drop-in fix for backdrop-filter in Outlook Classic. Design so the email still reads without it.
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backdrop-filter is not among the 24 features we have screenshotted on real installs. The ones we have →
All 21 clients, problems first
| Client | Support |
|---|---|
| Gmail | Not supported |
| Gmail Android | Not supported |
| Gmail iOS | Not supported |
| Outlook 365 | Not supported |
| Outlook (New) | Not supported |
| Outlook Classic | Not supported |
| Outlook iOS | Not supported |
| Outlook Android | Not supported |
| Yahoo Mail | Not supported |
| Yahoo Mail Android | Not supported |
| Yahoo Mail iOS | Not supported |
| AOL Mail | Not supported |
| Thunderbird | Untested |
| HEY Mail | Untested |
| Fastmail | Untested |
Works in 6: Outlook for Mac, Apple Mail, Apple Mail iOS and 3 more. Show all
| Client | Support |
|---|---|
| Outlook for Mac | Works |
| Apple Mail | Works See caveat 1 |
| Apple Mail iOS | Works See caveat 1 |
| Samsung Mail | Works |
| Proton Mail | Works |
| Superhuman | Works |
Caveats (1)
- 1. Apple Mail, Apple Mail iOS: Works with prefix
-webkit
Caveats as recorded by caniemail (MIT), one entry per wording.
How backdrop-filter behaves
backdrop-filter applies graphical effects (blur, saturation, contrast) to the area behind an element, producing the frosted-glass look popularized by modern OS UIs. In email, support is essentially limited to Apple Mail, every other major client ignores it.
- Apple Mail (macOS and iOS) supports backdrop-filter via -webkit-backdrop-filter.
- Outlook, Gmail, Yahoo, and most mobile clients render the element with no backdrop effect.
- Performance can suffer on lower-end iOS devices when stacking backdrop-filter with translucent elements.
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