border-spacing in Fastmail
Untested caniemail has no record for border-spacing in Fastmail.
Works in 17 of 21 · not supported in 2 · 2 untested
Which clients
- Works
- Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook iOS, Outlook Android, Apple Mail, Apple Mail iOS, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Thunderbird, Proton Mail, AOL Mail, Superhuman
- Not supported
- Outlook Classic, Outlook for Mac
- Untested
- HEY Mail, Fastmail
What to do instead in Fastmail
Use the cellspacing HTML attribute instead of border-spacing CSS
<table cellspacing="8" style="border-collapse: separate;">
<tr><td>Cell</td></tr>
</table>Show the original
<table style="border-spacing: 8px; border-collapse: separate;">
<tr><td>Cell</td></tr>
</table>A free account opens all 21 clients and keeps your checks for 7 days. Create a free account →
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Questions
- How many email clients support border-spacing?
- It works in 17 of 21, not supported in Outlook Classic and Outlook for Mac, 2 untested.
- What do I use instead of border-spacing in Fastmail?
- Use the cellspacing HTML attribute instead of border-spacing CSS.
- Does border-spacing work in Apple Mail?
- border-spacing works in Apple Mail. Closest to Fastmail: Apple Mail, which agrees on 192 of the 235 features both are tested on.
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Real captures 14 Oct 2026 on 10 installs · caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 20 Dec 2023 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping