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CSS property · data last changed 10 Nov 2026

[align] in email clients

Works in 17 of 21. Partial in Outlook for Mac, HEY Mail and Proton Mail. Untested in Superhuman.

Your reader in Outlook for Mac may not see [align] the way you wrote it, even if it looks right where you tested it.

caniemail (MIT) via @emailens/engine 0.18.22

What to do instead in Outlook for Mac

  • Partial. left and right do not work on <table> elements. Use float:left or float:right styles instead.

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[align] is not among the 24 features we have screenshotted on real installs. The ones we have →

All 21 clients, problems first

ClientSupport
Outlook for Mac Partial See caveat 1
HEY Mail Partial See caveat 2
Proton Mail Partial See caveat 3
Superhuman Untested
Works in 17: Gmail, Gmail Android, Gmail iOS and 14 more. Show all
ClientSupport
Gmail Works
Gmail Android Works
Gmail iOS Works
Outlook 365 Works
Outlook (New) Works
Outlook Classic Works
Outlook iOS Works
Outlook Android Works
Apple Mail Works
Apple Mail iOS Works
Yahoo Mail Works
Yahoo Mail Android Works
Yahoo Mail iOS Works
Samsung Mail Works
Thunderbird Works
AOL Mail Works
Fastmail Works

Caveats (3)

  1. 1. Outlook for Mac: Partial. left and right do not work on <table> elements. Use float:left or float:right styles instead.
  2. 2. HEY Mail: Partial. Not supported on <img> elements.
  3. 3. Proton Mail: Partial. <img> elements are wrapped in a <span> so left and right values have no effect.

Caveats as recorded by caniemail (MIT), one entry per wording.

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 10 Nov 2021 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping