Online/offline status

Events to indicate when the user's connected (online and offline events) and the navigator.onLine property to see current status.

Spec	https://html.spec.whatwg.org/multipage/browsers.html#browser-state
Status	WHATWG Living Standard

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 ⁽²⁾	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 ⁽³⁾	41		23
		39 ⁽³⁾	40		22
		38 ⁽³⁾	39		21
		37 ⁽³⁾	38		20
		36 ⁽³⁾	37		19
		35 ⁽³⁾	36		18
		34 ⁽³⁾	35		17
		33 ⁽³⁾	34		16
		32 ⁽³⁾	33		15
		31 ⁽³⁾	32		12.1
		30 ⁽³⁾	31		12
		29 ⁽³⁾	30		11.6
		28 ⁽³⁾	29		11.5
		27 ⁽³⁾	28		11.1
		26 ⁽³⁾	27		11
		25 ⁽³⁾	26		10.6
		24 ⁽³⁾	25		10.5
		23 ⁽³⁾	24		10.0-10.1
		22 ⁽³⁾	23		9.5-9.6
		21 ⁽³⁾	22		9
		20 ⁽³⁾	21
		19 ⁽³⁾	20
		18 ⁽³⁾	19
		17 ⁽³⁾	18
		16 ⁽³⁾	17
		15 ⁽³⁾	16
		14 ⁽³⁾	15
		13 ⁽³⁾	14
		12 ⁽³⁾	13
		11 ⁽³⁾	12
		10 ⁽³⁾	11
		9 ⁽³⁾	10
		8 ⁽³⁾	9
		7 ⁽³⁾	8
		6 ⁽³⁾	7
		5 ⁽³⁾	6
		4 ⁽³⁾	5
		3.6	4
		3.5
		3
		2

Notes

"online" does not always mean connection to the internet, it can also just mean connection to some network.

Early versions of Chrome and Safari always reported "true" for navigator.onLine

Safari 7.0 supports only the event listener on window, and not on document.body
Seems to support navigator.onLine but not online/offline events.
IE8 only supports the online/offline events on document.body, rather than window.
Desktop Firefox responds to the status of its "Work Offline" mode. If not in that mode, navigator.onLine is always true, regardless of the actual network connectivity status. See bug for details.

Data by caniuse.com
Licensed under the Creative Commons Attribution License v4.0.
https://caniuse.com/online-status