HTTP Public Key Pinning

Declare that a website's HTTPS certificate should only be treated as valid if the public key is contained in a list specified over HTTP to prevent MITM attacks that use valid CA-issued certificates.

Spec	https://tools.ietf.org/html/rfc7469
Status	Other

IE	Edge	Firefox	Chrome	Safari	Opera
			98
		95	97
		94	96	TP
11	95	93	95	15	80
10	94	92	94	14.1	79
9	93	91	93	14	78
8	92	90	92	13.1	77
Show all
7	91	89	91	13	76
6	90	88	90	12.1	75
5.5	89	87	89	12	74
	88	86	88	11.1	73
	87	85	87	11	72
	86	84	86	10.1	71
	85	83	85	10	70
	84	82	84	9.1	69
	83	81	83	9	68
	81	80	81	8	67
	80	79	80	7.1	66
	79	78	79	7	65
	18	77	78	6.1	64
	17	76	77	6	63
	16	75	76	5.1	62
	15	74	75	5	60
	14	73	74	4	58
	13	72	73	3.2	57
	12	71	72	3.1	56
		70	71		55
		69	70		54
		68	69		53
		67	68		52
		66	67		51
		65	66		50
		64	65		49
		63	64		48
		62	63		47
		61	62		46
		60	61		45
		59	60		44
		58	59		43
		57	58		42
		56	57		41
		55	56		40
		54	55		39
		53	54		38
		52	53		37
		51	52		36
		50	51		35
		49	50		34
		48	49		33
		47	48		32
		46	47		31
		45	46		30
		44	45		29
		43	44		28
		42	43		27
		41	42		26
		40	41		25
		39	40		24
		38	39		23
		37	38		22
		36	37		21
		35	36		20
		34	35		19
		33	34		18
		32	33		17
		31	32		16
		30	31		15
		29	30		12.1
		28	29		12
		27	28		11.6
		26	27		11.5
		25	26		11.1
		24	25		11
		23	24		10.6
		22	23		10.5
		21	22		10.0-10.1
		20	21		9.5-9.6
		19	20		9
		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	all	94	10	64	94	92	11	12.12	15.0	10.4	7.12	2.5
14.5-14.8		4.4.3-4.4.4	7	12.1			10		14.0
14.0-14.4		4.4		12					13.0
13.4-13.7		4.2-4.3		11.5					12.0
Show all
13.3		4.1		11.1					11.1-11.2
13.2		4		11					10.1
13.0-13.1		3		10					9.2
12.2-12.5		2.3							8.2
12.0-12.1		2.2							7.2-7.4
11.3-11.4		2.1							6.2-6.4
11.0-11.2									5.0-5.4
10.3									4
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

All browsers have removed support. The header was too complicated to use, and when incorrectly implemented, could completely block websites for longer periods of time.

Certificate transparency is widely used and tries to provide the same security by very different means.

Resources

• MDN Web Docs - Public Key Pinning
• Scott Helme article on the issues of HPKP