CSS3 Box-sizing

Method of specifying whether or not an element's borders and padding should be included in size units

Spec	https://www.w3.org/TR/css-sizing/#box-sizing
Status	W3C Working Draft

IE	Edge	Firefox	Chrome	Safari	Opera
		147	144
		146	143	TP
		145	142	26.1
11	141	144	141	26.0	122
10	140	143	140	18.5-18.6	121
9	139	142	139	18.4	120
8	138	141	138	18.3	119
Show all
7	137	140	137	18.2	118
6	136	139	136	18.1	117
5.5	135	138	135	18.0	116
	134	137	134	17.6	115
	133	136	133	17.5	114
	132	135	132	17.4	113
	131	134	131	17.3	112
	130	133	130	17.2	111
	129	132	129	17.1	110
	128	131	128	17.0	109
	127	130	127	16.6	108
	126	129	126	16.5	107
	125	128	125	16.4	106
	124	127	124	16.3	105
	123	126	123	16.2	104
	122	125	122	16.1	103
	121	124	121	16.0	102
	120	123	120	15.6	101
	119	122	119	15.5	100
	118	121	118	15.4	99
	117	120	117	15.2-15.3	98
	116	119	116	15.1	97
	115	118	115	15	96
	114	117	114	14.1	95
	113	116	113	14	94
	112	115	112	13.1	93
	111	114	111	13	92
	110	113	110	12.1	91
	109	112	109	12	90
	108	111	108	11.1	89
	107	110	107	11	88
	106	109	106	10.1	87
	105	108	105	10	86
	104	107	104	9.1	85
	103	106	103	9	84
	102	105	102	8	83
	101	104	101	7.1	82
	100	103	100	7	81
	99	102	99	6.1	80
	98	101	98	6	79
	97	100	97	5.1	78
	96	99	96	5 (*)	77
	95	98	95	4 (*)	76
	94	97	94	3.2 (*)	75
	93	96	93	3.1 (*)	74
	92	95	92		73
	91	94	91		72
	90	93	90		71
	89	92	89		70
	88	91	88		69
	87	90	87		68
	86	89	86		67
	85	88	85		66
	84	87	84		65
	83	86	83		64
	81	85	81		63
	80	84	80		62
	79	83	79		60
	18	82	78		58
	17	81	77		57
	16	80	76		56
	15	79	75		55
	14	78	74		54
	13	77	73		53
	12	76	72		52
		75	71		51
		74	70		50
		73	69		49
		72	68		48
		71	67		47
		70	66		46
		69	65		45
		68	64		44
		67	63		43
		66	62		42
		65	61		41
		64	60		40
		63	59		39
		62	58		38
		61	57		37
		60	56		36
		59	55		35
		58	54		34
		57	53		33
		56	52		32
		55	51		31
		54	50		30
		53	49		29
		52	48		28
		51	47		27
		50	46		26
		49	45		25
		48	44		24
		47	43		23
		46	42		22
		45	41		21
		44	40		20
		43	39		19
		42	38		18
		41	37		17
		40	36		16
		39	35		15
		38	34		12.1
		37	33		12
		36	32		11.6
		35	31		11.5
		34	30		11.1
		33	29		11
		32	28		10.6
		31	27		10.5
		30	26		10.0-10.1
		29	25		9.5-9.6
		28 (*)	24		9
		27 (*)	23
		26 (*)	22
		25 (*)	21
		24 (*)	20
		23 (*)	19
		22 (*)	18
		21 (*)	17
		20 (*)	16
		19 (*)	15
		18 (*)	14
		17 (*)	13
		16 (*)	12
		15 (*)	11
		14 (*)	10
		13 (*)	9 (*)
		12 (*)	8 (*)
		11 (*)	7 (*)
		10 (*)	6 (*)
		9 (*)	5 (*)
		8 (*)	4 (*)
		7 (*)
		6 (*)
		5 (*)
		4 (*)
		3.6 (*)
		3.5 (*)
		3 (*)
		2 (*)

Safari on iOS	Opera Mini	Android Browser	Blackberry Browser	Opera Mobile	Android Chrome	Android Firefox	IE Mobile	Android UC Browser	Samsung Internet	QQ Browser	Baidu Browser	KaiOS Browser
26.1
26.0	all	141	10	80	141	143	11	15.5	28	14.9	13.52	3.0-3.1
18.5-18.6		4.4.3-4.4.4	7 (*)	12.1			10		27			2.5
18.4		4.4		12					26
18.3		4.2-4.3		11.5					25
Show all
18.2		4.1		11.1					24
18.1		4		11					23
18.0		3 (*)		10					22
17.6-17.7		2.3 (*)							21
17.5		2.2 (*)							20
17.4		2.1 (*)							19.0
17.3									18.0
17.2									17.0
17.1									16.0
17.0									15.0
16.6-16.7									14.0
16.5									13.0
16.4									12.0
16.3									11.1-11.2
16.2									10.1
16.1									9.2
16.0									8.2
15.6-15.8									7.2-7.4
15.5									6.2-6.4
15.4									5.0-5.4
15.2-15.3									4
15.0-15.1
14.5-14.8
14.0-14.4
13.4-13.7
13.3
13.2
13.0-13.1
12.2-12.5
12.0-12.1
11.3-11.4
11.0-11.2
10.3
10.0-10.2
9.3
9.0-9.2
8.1-8.4
8
7.0-7.1
6.0-6.1
5.0-5.1
4.2-4.3 (*)
4.0-4.1 (*)
3.2 (*)

Notes

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.

^* Partial support with prefix.

Bugs

• Android browsers do not calculate correctly the dimensions (width and height) of the HTML select element.

• Safari 6.0.x does not use box-sizing on elements with display: table;

• IE9 will subtract the width of the scrollbar to the width of the element when set to position: absolute / fixed , overflow: auto / overflow-y: scroll

• IE 8 ignores box-sizing: border-box if min/max-width/height is used.

• Chrome has problems selecting options from the select element when using box-sizing: border-box and browser zoom level is less than 100%.

• In IE8, the min-width property applies to content-box even if box-sizing is set to border-box.

• In Chrome, the inherit value doesn't work on elements inside details, this could lead to unexpected behaviour when box-sizing: inherit is used in a universal selector, see https://bugs.chromium.org/p/chromium/issues/detail?id=589475

Resources

• MDN Web Docs - CSS box-sizing
• Blog post
• Polyfill for IE
• CSS Tricks
• WebPlatform Docs