box-sizing in Apple Mail iOS
Works box-sizing works in Apple Mail iOS.
Works in 16 of 21 · not supported in 5
Which clients
- Works
- Gmail, Gmail Android, Gmail iOS, Outlook 365, Outlook (New), Outlook iOS, Outlook Android, Outlook for Mac, Apple Mail, Apple Mail iOS, Samsung Mail, Thunderbird, HEY Mail, Proton Mail, Fastmail, Superhuman
- Not supported
- Outlook Classic, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, AOL Mail
The fix for the clients that need it
Needed in 5 of 21: Outlook Classic, Yahoo Mail, Yahoo Mail Android and 2 more.
Account for padding in width manually (no box-sizing)
<div style="width: 300px;">
<div style="padding: 20px;">
Content; padding on inner element
</div>
</div>Show the original
<div style="width: 300px; padding: 20px;
box-sizing: border-box;">
Content; total width stays 300px
</div>A free account opens all 21 clients and keeps your checks for 7 days. Create a free account →
What Apple Mail iOS does with box-sizing
The Emailens probe for box-sizing on a real install counted as Apple Mail iOS, captured 14 Oct 2026. It shows the probe, not the fix. Where box-sizing is supported it shows: both bars the same width.
caniemail: box-sizing works in Apple Mail iOS.
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Your next question
- Does inline-size work in Apple Mail iOS?
Works in 4 of 21 · not supported in 16 · 1 untested
- Does cursor work in Apple Mail iOS?
Works in 2 of 21 · partial in 4 · not supported in 10 · 5 untested
- Does hyphenate-limit-chars work in Apple Mail iOS?
Works in 1 of 21 · not supported in 17 · 3 untested
- Does resize work in Apple Mail iOS?
Works in 1 of 21 · partial in 1 · not supported in 16 · 3 untested
- Does text-justify work in Apple Mail iOS?
Works in 0 of 21 · partial in 4 · not supported in 13 · 4 untested
- Does :focus work in Apple Mail iOS?
Works in 10 of 21 · partial in 3 · not supported in 7 · 1 untested
Every feature in Apple Mail iOS · box-sizing in every client
Questions
- How many email clients support box-sizing?
- It works in 16 of 21, not supported in 5.
- Does box-sizing work in Apple Mail?
- box-sizing works in Apple Mail. Closest to Apple Mail iOS: Apple Mail, which agrees on 284 of the 298 features both are tested on.
To see what in your email Apple Mail iOS does not support, paste the whole email.
No signup · Five clients free, Outlook Classic included · All 21 with an account
The checker needs a computer screen.
Real captures 14 Oct 2026 on 11 installs · caniemail (MIT) via @emailens/engine 0.18.22 · tested upstream 28 Feb 2019 · data last changed 10 Nov 2026 · Outlook (New) cells are the engine's mapping