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Emailens

CSS property · data last changed 10 Nov 2026

font-stretch in email clients

Works in 10 of 21. Not supported in Gmail Android, Outlook Classic, Outlook Android and 5 more. Untested in HEY Mail, Fastmail and Superhuman.

Your reader in Outlook Classic sees the email without font-stretch, even if it looks right where you tested it.

caniemail (MIT) via @emailens/engine 0.18.22

What to do instead in Outlook Classic

There is no drop-in fix for font-stretch in Outlook Classic. Design so the email still reads without it.

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font-stretch is not among the 24 features we have screenshotted on real installs. The ones we have →

All 21 clients, problems first

ClientSupport
Gmail Android Not supported
Outlook Classic Not supported
Outlook Android Not supported
Yahoo Mail Not supported
Yahoo Mail Android Not supported
Yahoo Mail iOS Not supported
Samsung Mail Not supported
AOL Mail Not supported
HEY Mail Untested
Fastmail Untested
Superhuman Untested
Works in 10: Gmail, Gmail iOS, Outlook 365 and 7 more. Show all
ClientSupport
Gmail Works See caveat 1
Gmail iOS Works
Outlook 365 Works See caveat 1
Outlook (New) Works See caveat 1
Outlook iOS Works
Outlook for Mac Works
Apple Mail Works
Apple Mail iOS Works
Thunderbird Works
Proton Mail Works See caveat 1

Caveats (1)

  1. 1. Gmail, Outlook 365, Outlook (New), Proton Mail: Partial. Depends on the browser. There is currently a bug in Chrome/Edge where font-stretch does not work for variable fonts.

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

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caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 23 Sep 2023 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping