How many email clients support ?

It works in 16 of 21, partial in 5.

Does work in Gmail Android?

is partly supported in Gmail Android. Closest to Gmail iOS: Gmail Android, which agrees on 273 of the 300 features both are tested on.

<style> in Gmail iOS

Partial <style> is partly supported in Gmail iOS.

Not supported inside the <body>.

Works in 16 of 21 · partial in 5

Which clients

Works: Outlook 365, Outlook (New), Outlook iOS, Outlook Android, Outlook for Mac, Apple Mail, Apple Mail iOS, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Thunderbird, HEY Mail, AOL Mail, Fastmail, Superhuman
Partial: Gmail, Gmail Android, Gmail iOS, Outlook Classic, Proton Mail

Your reader in Gmail iOS may not see <style> the way you wrote it, even if it looks right where you tested it.

What to do instead in Gmail iOS

Inline CSS for Gmail compatibility

instead

6 lines

<div style="background-color: #6d28d9; padding: 32px;">
  <h1 style="color: #fff; font-size: 24px;
             font-family: Arial, sans-serif; margin: 0;">
    Hello
  </h1>
</div>

Show the original

before

7 lines

<style>
  .header { background-color: #6d28d9; padding: 32px; }
  .title  { color: #fff; font-size: 24px; }
</style>
<div class="header">
  <h1 class="title">Hello</h1>
</div>

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What Gmail iOS does with <style>

caniemail record, tested upstream 27 Jul 2023

Partial. Not supported inside the <body>.
Partial. Not supported with non Google accounts.

Your next question

Every feature in Gmail iOS · <style> in every client

Questions

How many email clients support <style>?: It works in 16 of 21, partial in 5.
What do I use instead of <style> in Gmail iOS?: Inline CSS for Gmail compatibility.
Does <style> work in Gmail Android?: <style> is partly supported in Gmail Android. Closest to Gmail iOS: Gmail Android, which agrees on 273 of the 300 features both are tested on.

To see what else in your email Gmail iOS does not support, paste the whole email.

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 27 Jul 2023 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping