CSS Properties

animation

CSS property · 6 supported, 1 partial, 14 unsupported across 21 clients

As of Sep 2, 2026, animation fails or degrades in 15 of 21 email clients, treat it as progressive enhancement, never structure.

2/7 webmail, 2/6 desktop, 2/8 mobile clients support animation fully.
Unsupported in Gmail, Gmail Android, Gmail iOS, Outlook 365 and 10 more.
Partial in Superhuman, behavior differs from browsers, test before relying on it.
Outlook Classic (Word engine, supported to at least 2029) does not fully support animation, and its replacement changes little here; see the deprecation diff.
Documented before/after fixes on this page cover 21 clients, including Gmail and Gmail Android.
Across all clients, only 6 of 298 tracked HTML/CSS features render identically everywhere.

Source: caniemail.com (MIT), via the Emailens engine. Last tested upstream Apr 7, 2026, synced by Emailens Sep 2, 2026.

Client Support

Client	Category	Engine	Support
Gmail	webmail	Gmail Web	Unsupported
Gmail Android	mobile	Gmail Mobile	Unsupported
Gmail iOS	mobile	Gmail Mobile	Unsupported
Outlook 365	webmail	Outlook Web	Unsupported
Outlook (New)	desktop	Outlook Web	Unsupported
Outlook Classic	desktop	Microsoft Word	Unsupported
Outlook iOS	mobile	Outlook Mobile	Unsupported
Outlook Android	mobile	Outlook Mobile	Unsupported
Outlook for Mac	desktop	WebKit	Supported
Apple Mail	desktop	WebKit	Supported
Apple Mail iOS	mobile	WebKit	Supported
Yahoo Mail	webmail	Yahoo	Unsupported
Yahoo Mail Android	mobile	Yahoo	Unsupported
Yahoo Mail iOS	mobile	Yahoo	Unsupported
Samsung Mail	mobile	Samsung	Supported
Thunderbird	desktop	Gecko	Unsupported
HEY Mail	webmail	WebKit	Supported
Proton Mail	webmail	Proton	Unsupported
AOL Mail	webmail	AOL	Unsupported
Fastmail	webmail	Fastmail	Supported
Superhuman	desktop	Blink	Partial

Client-by-client behaviour for animation

Fully supports animation (6): Outlook for Mac, Apple Mail, Apple Mail iOS, Samsung Mail, HEY Mail, Fastmail.

Partial support (1): Superhuman. Expect rendering quirks unique to each engine. Partial support typically means a subset of values, an ignored shorthand, or sanitizer-specific rewrites.

No support (14): Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook Classic, Outlook iOS, Outlook Android, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Thunderbird, Proton Mail, AOL Mail. Plan fallbacks for these clients before relying on animation in production sends.

Fixes & Workarounds

Gmail

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Gmail Android

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Gmail iOS

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Outlook 365

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Outlook (New)

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Outlook Classic

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Outlook iOS

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Outlook Android

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Yahoo Mail

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Yahoo Mail Android

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Yahoo Mail iOS

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Thunderbird

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Proton Mail

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

AOL Mail

Unsupported

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Superhuman

Partial

CSS animations are not supported. Use animated GIFs instead.

Before (Broken)

before.html

5 lines

<style>
  @keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
  .badge { animation: pulse 2s infinite; }
</style>
<span class="badge">New!</span>

After (Fixed)

fixed.html

4 lines

<!-- Use an animated GIF for the effect -->
<img src="https://example.com/badge-animated.gif"
  width="60" height="24" alt="New!"
  style="display: inline-block; border: 0;" />

Replace CSS animation with an animated GIF

Production guidance for animation

animation is a CSS property. Across the email client matrix, 6 of 21 tracked clients support it fully, 1 only partially, and 14 not at all. The clients most likely to require a workaround for this feature are Gmail, Gmail Android, Gmail iOS. Each of them needs a tailored fallback. See the per-client examples above for the specific code fix Emailens recommends.

When in doubt, ship a baseline that renders without animation and treat it as progressive enhancement on clients where support is verified. Emailens automatically detects cross-client divergence on this feature when you preview an email, so you can see exactly which template paths break before a campaign goes out.

Related Features

!important accent-color align-items aspect-ratio backdrop-filter background background-blend-mode background-clip

Check your own HTML for animation

Paste your own, or run the sample below. Analyzed in this page, with no signup and nothing stored.

Zero-Friction Engine Preview

Test your animation layout across 21 email clients

Preview rendering, catch CSS issues, and see how animation displays across Outlook, Gmail, and Apple Mail. Free, no account needed.

Instant live preview · No signup required · 21 email engines

Last tested upstream: Apr 7, 2026 · Last synced by Emailens: Sep 2, 2026

caniemail.com (MIT) records Apr 7, 2026 as the last time animation was tested in a real client, less than a year before this sync. Syncing copies that result forward, it does not re-test it. Carried in @emailens/engine data v0.12.2.