CSS3 Box-sizing
- WDMethod of specifying whether or not an element's borders and padding should be included in size units
Chrome
- ✅ 4 - 9: Supported
- ✅ 10 - 146: Supported
- ✅ 147: Supported
- ✅ 148 - 150: Supported
Edge
- ✅ 12 - 145: Supported
- ✅ 146: Supported
Safari
- ✅ 3.1 - 5: Supported
- ✅ 5.1 - 26.3: Supported
- ✅ 26.4: Supported
- ✅ 26.5 - TP: Supported
Firefox
- ✅ 2 - 28: Supported
- ✅ 29 - 148: Supported
- ✅ 149: Supported
- ✅ 150 - 152: Supported
Opera
- ❌ 9: Not supported
- ✅ 9.5 - 126: Supported
- ✅ 127: Supported
IE
- ❌ 5.5 - 7: Not supported (but has polyfill available)
- ✅ 8 - 10: Supported
- ✅ 11: Supported
Chrome for Android
- ✅ 147: Supported
Safari on iOS
- ✅ 3.2 - 4.3: Supported
- ✅ 5 - 26.3: Supported
- ✅ 26.4: Supported
- ✅ 26.5: Supported
Samsung Internet
- ✅ 4 - 28: Supported
- ✅ 29: Supported
Opera Mini
- ✅ all: Supported
Opera Mobile
- ✅ 10 - 12.1: Supported
- ✅ 80: Supported
UC Browser for Android
- ✅ 15.5: Supported
Android Browser
- ✅ 2.1 - 3: Supported
- ✅ 4 - 4.4.4: Supported
- ✅ 147: Supported
Firefox for Android
- ✅ 149: Supported
QQ Browser
- ✅ 14.9: Supported
Baidu Browser
- ✅ 13.52: Supported
KaiOS Browser
- ✅ 2.5: Supported
- ✅ 3: Supported
Firefox versions before 57 also supported the padding-box value for box-sizing, though this value was been removed from the specification and later versions of the browser.