Note:

This reference is primarily for US keyboards. There are many keyboard layouts internationally which include not only different characters, but standard characters in different places. And there can be differences between browsers and browser versions.

Key Code Generator CCBot/2.0 (https://commoncrawl.org/faq/)

Key Code Key Code Key Code
Backspace
 8
E
 69
NumPad 8
 104
Tab
 9
F
 70
NumPad 9
 105
Enter
 13
G
 71
NumPad *
 106
Shift
 16
H
 72
NumPad +
 107
Ctrl
 17
I
 73
NumPad -
 109
Alt
 18
J
 74
NumPad .
 110
Pause/Break
 19
K
 75
NumPad /
 111
Caps Lock
 20
L
 76
F1
 112
Esc
 27
M
 77
F2
 113
Page Up
 33
N
 78
F3
 114
Page Down
 34
O
 79
F4
 115
End
 35
P
 80
F5
 116
Home
 36
Q
 81
F6
 117
←
 37
R
 82
F7
 118
↑
 38
S
 83
F8
 119
→
 39
T
 84
F9
 120
↓
 40
U
 85
F10
 121
Insert
 45
V
 86
F11
 122
Delete
 46
W
 87
F12
 123
0
)
 48
X
 88
Num Lock
 144
1
!
 49
Y
 89
Scroll Lock
 145
2
@
 50
Z
 90
;
:
 186
3
#
 51
Left WinKey
 91
=
+
 187
4
$
 52
Right WinKey
 92
,
<
 188
5
%
 53
Select
 93
-
_
 189
6
^
 54
NumPad 0
 96
.
>
 190
7
&
 55
NumPad 1
 97
/
?
 191
8
*
 56
NumPad 2
 98
`
~
 192
9
(
 57
NumPad 3
 99
[
{
 219
A
 65
NumPad 4
 100
\
|
 220
B
 66
NumPad 5
 101
]
}
 221
C
 67
NumPad 6
 102
'
"
 222
D
 68
NumPad 7
 103   
Code Key Code Key Code Key
8
Backspace
 69
E
 104
NumPad 8
9
Tab
 70
F
 105
NumPad 9
13
Enter
 71
G
 106
NumPad *
16
Shift
 72
H
 107
NumPad +
17
Ctrl
 73
I
 109
NumPad -
18
Alt
 74
J
 110
NumPad .
19
Pause/Break
 75
K
 111
NumPad /
20
Caps Lock
 76
L
 112
F1
27
Esc
 77
M
 113
F2
33
Page Up
 78
N
 114
F3
34
Page Down
 79
O
 115
F4
35
End
 80
P
 116
F5
36
Home
 81
Q
 117
F6
37
←
 82
R
 118
F7
38
↑
 83
S
 119
F8
39
→
 84
T
 120
F9
40
↓
 85
U
 121
F10
45
Insert
 86
V
 122
F11
46
Delete
 87
W
 123
F12
48
0
)
 88
X
 144
Num Lock
49
1
!
 89
Y
 145
Scroll Lock
50
2
@
 90
Z
 186
;
:
51
3
#
 91
Left WinKey
 187
=
+
52
4
$
 92
Right WinKey
 188
,
<
53
5
%
 93
Select
 189
-
_
54
6
^
 96
NumPad 0
 190
.
>
55
7
&
 97
NumPad 1
 191
/
?
56
8
*
 98
NumPad 2
 192
`
~
57
9
(
 99
NumPad 3
 219
[
{
65
A
 100
NumPad 4
 220
\
|
66
B
 101
NumPad 5
 221
]
}
67
C
 102
NumPad 6
 222
'
"
68
D
 103
NumPad 7
   
The following javascript code snippet creates an array of objects containing the key code (id) and the key character (name). 
/* Key Code list by http://www.javascriptkeycode.com */
var keycodes = [{"id":8,"name":"Backspace"},{"id":9,"name":"Tab"},{"id":13,"name":"Enter"},{"id":16,"name":"Shift"},{"id":17,"name":"Ctrl"},{"id":18,"name":"Alt"},{"id":19,"name":"Pause/Break"},{"id":20,"name":"Caps Lock"},{"id":27,"name":"Esc"},{"id":33,"name":"Page Up"},{"id":34,"name":"Page Down"},{"id":35,"name":"End"},{"id":36,"name":"Home"},{"id":37,"name":"←"},{"id":38,"name":"↑"},{"id":39,"name":"→"},{"id":40,"name":"↓"},{"id":45,"name":"Insert"},{"id":46,"name":"Delete"},{"id":48,"name":"0"},{"id":49,"name":"1"},{"id":50,"name":"2"},{"id":51,"name":"3"},{"id":52,"name":"4"},{"id":53,"name":"5"},{"id":54,"name":"6"},{"id":55,"name":"7"},{"id":56,"name":"8"},{"id":57,"name":"9"},{"id":65,"name":"A"},{"id":66,"name":"B"},{"id":67,"name":"C"},{"id":68,"name":"D"},{"id":69,"name":"E"},{"id":70,"name":"F"},{"id":71,"name":"G"},{"id":72,"name":"H"},{"id":73,"name":"I"},{"id":74,"name":"J"},{"id":75,"name":"K"},{"id":76,"name":"L"},{"id":77,"name":"M"},{"id":78,"name":"N"},{"id":79,"name":"O"},{"id":80,"name":"P"},{"id":81,"name":"Q"},{"id":82,"name":"R"},{"id":83,"name":"S"},{"id":84,"name":"T"},{"id":85,"name":"U"},{"id":86,"name":"V"},{"id":87,"name":"W"},{"id":88,"name":"X"},{"id":89,"name":"Y"},{"id":90,"name":"Z"},{"id":91,"name":"Left WinKey"},{"id":92,"name":"Right WinKey"},{"id":93,"name":"Select"},{"id":96,"name":"NumPad 0"},{"id":97,"name":"NumPad 1"},{"id":98,"name":"NumPad 2"},{"id":99,"name":"NumPad 3"},{"id":100,"name":"NumPad 4"},{"id":101,"name":"NumPad 5"},{"id":102,"name":"NumPad 6"},{"id":103,"name":"NumPad 7"},{"id":104,"name":"NumPad 8"},{"id":105,"name":"NumPad 9"},{"id":106,"name":"NumPad *"},{"id":107,"name":"NumPad +"},{"id":109,"name":"NumPad -"},{"id":110,"name":"NumPad ."},{"id":111,"name":"NumPad /"},{"id":112,"name":"F1"},{"id":113,"name":"F2"},{"id":114,"name":"F3"},{"id":115,"name":"F4"},{"id":116,"name":"F5"},{"id":117,"name":"F6"},{"id":118,"name":"F7"},{"id":119,"name":"F8"},{"id":120,"name":"F9"},{"id":121,"name":"F10"},{"id":122,"name":"F11"},{"id":123,"name":"F12"},{"id":144,"name":"Num Lock"},{"id":145,"name":"Scroll Lock"},{"id":186,"name":";"},{"id":187,"name":"="},{"id":188,"name":","},{"id":189,"name":"-"},{"id":190,"name":"."},{"id":191,"name":"/"},{"id":192,"name":"`"},{"id":219,"name":"["},{"id":220,"name":"\\"},{"id":221,"name":"]"},{"id":222,"name":"'"}];

A key code is an implementation dependent numerical code identifying the unmodified value of the pressed key. The Javascript keydown, keypress, and keyup events specify which key (key code) was pressed and if any modifiers (shift, alt, ctrl) are pressed at the same time. It's important to note that the key code is a unique code for the key itself and doesn't change if a modifier is pressed. i.e. "!" has the same key code as "1".

Because different keyboards, systems, and implementations can use different values for the different keys, care should be exercised when using key codes.