Case-insensitive CSS attribute selectors

Including an i before the ] in a CSS attribute selector causes the attribute value to be matched in an ASCII-case-insensitive manner. For example, [b="xyz" i] would match both <a b="xyz"> and <a b="XYZ">.

Spec	https://www.w3.org/TR/selectors-4/#attribute-case
Status	W3C Working Draft

IE	Edge	Firefox	Chrome	Safari	Opera
			103
		100	102
		99	101	TP
11	99	98	100	15.4	83
10	98	97	99	15.2-15.3	82
9	97	96	98	15.1	81
8	96	95	97	15	80
Show all
7	95	94	96	14.1	79
6	94	93	95	14	78
5.5	93	92	94	13.1	77
	92	91	93	13	76
	91	90	92	12.1	75
	90	89	91	12	74
	89	88	90	11.1	73
	88	87	89	11	72
	87	86	88	10.1	71
	86	85	87	10	70
	85	84	86	9.1	69
	84	83	85	9	68
	83	82	84	8	67
	81	81	83	7.1	66
	80	80	81	7	65
	79	79	80	6.1	64
	18	78	79	6	63
	17	77	78	5.1	62
	16	76	77	5	60
	15	75	76	4	58
	14	74	75	3.2	57
	13	73	74	3.1	56
	12	72	73		55
		71	72		54
		70	71		53
		69	70		52
		68	69		51
		67	68		50
		66	67		49
		65	66		48
		64	65		47
		63	64		46
		62	63		45
		61	62		44
		60	61		43
		59	60		42
		58	59		41
		57	58		40
		56	57		39
		55	56		38
		54	55		37
		53	54		36
		52	53		35
		51	52		34
		50	51		33
		49	50		32
		48	49		31
		47	48		30
		46	47		29
		45	46		28
		44	45		27
		43	44		26
		42	43		25
		41	42		24
		40	41		23
		39	40		22
		38	39		21
		37	38		20
		36	37		19
		35	36		18
		34	35		17
		33	34		16
		32	33		15
		31	32		12.1
		30	31		12
		29	30		11.6
		28	29		11.5
		27	28		11.1
		26	27		11
		25	26		10.6
		24	25		10.5
		23	24		10.0-10.1
		22	23		9.5-9.6
		21	22		9
		20	21
		19	20
		18	19
		17	18
		16	17
		15	16
		14	15
		13	14
		12	13
		11	12
		10	11
		9	10
		8	9
		7	8
		6	7
		5	6
		4	5
		3.6	4
		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
15.4	all	99	10	64	100	98	11	12.12	16.0	10.4	7.12	2.5
15.2-15.3		4.4.3-4.4.4	7	12.1			10		15.0
15.0-15.1		4.4		12					14.0
14.5-14.8		4.2-4.3		11.5					13.0
Show all
14.0-14.4		4.1		11.1					12.0
13.4-13.7		4		11					11.1-11.2
13.3		3		10					10.1
13.2		2.3							9.2
13.0-13.1		2.2							8.2
12.2-12.5		2.1							7.2-7.4
12.0-12.1									6.2-6.4
11.3-11.4									5.0-5.4
11.0-11.2									4
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

Resources

• MDN Web Docs - CSS case-insensitive
• JS Bin testcase
• MS Edge feature request on UserVoice