CSS property · data last changed 10 Nov 2026
[height] in email clients
Works in 18 of 21. Not supported in HEY Mail. Partial in Outlook Classic. Untested in Superhuman.
Safe to leave in: where it is not supported, the email renders the same.
caniemail (MIT) via @emailens/engine 0.18.22
What to do instead in Outlook Classic
- Buggy. Percentage width on
<img>elements are based on the physical file's width, not on the parent element's width. - Buggy. Sizes set in attributes don't scale in 120 dpi mode.
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[height] is not among the 24 features we have screenshotted on real installs. The ones we have →
All 21 clients, problems first
| Client | Support |
|---|---|
| HEY Mail | Not supported |
| Outlook Classic | Partial See caveat 1 |
| Superhuman | Untested |
Works in 18: Gmail, Gmail Android, Gmail iOS and 15 more. Show all
| Client | Support |
|---|---|
| Gmail | Works |
| Gmail Android | Works |
| Gmail iOS | Works |
| Outlook 365 | Works |
| Outlook (New) | Works |
| Outlook iOS | Works |
| Outlook Android | Works |
| Outlook for Mac | Works |
| Apple Mail | Works |
| Apple Mail iOS | Works |
| Yahoo Mail | Works |
| Yahoo Mail Android | Works |
| Yahoo Mail iOS | Works |
| Samsung Mail | Works |
| Thunderbird | Works |
| Proton Mail | Works |
| AOL Mail | Works |
| Fastmail | Works |
Caveats (1)
- 1. Outlook Classic: Buggy. Percentage width on
<img>elements are based on the physical file's width, not on the parent element's width. Buggy. Sizes set in attributes don't scale in 120 dpi mode.
Caveats as recorded by caniemail (MIT), one entry per wording.
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