When a key is pressed on the keyboard, a keycode is sent and the proper letter, number, character or action is decoded. Detecting this decimal number can be useful in scripting as it indicates which key has been pressed. A shortcut would be one example. Try it here.

Characters such as ½ can be useful in text content. The Unicode standards are adopted world wide but not all browsers are configured to view them correctly. These tables list the key, key combinations, resulting character, and the decimal keycode for a typical keyboard.

a = 97
b = 98
c = 99
d = 100
e = 101
f = 102
g = 103
h = 104
i = 105
j = 106
k = 107
l = 108
m = 109
n = 110
o = 111
p = 112
q = 113
r = 114
s = 115
t = 116
u = 117
v = 118
w = 119
x = 120
y = 121
z = 122

0 = 48
1 = 49
2 = 50
3 = 51
4 = 52
5 = 53
6 = 54
7 = 55
8 = 56
9 = 57

' = 39
, = 44
- = 45
. = 46
/ = 47
: = 58
= = 61
[ = 91
\ = 92
] = 93
` = 96

   return =   = 13
   escape =   = 27
space bar =   = 32

shift + a = A = 65
shift + b = B = 66
shift + c = C = 67
shift + d = D = 68
shift + e = E = 69
shift + f = F = 70
shift + g = G = 71
shift + h = H = 72
shift + i = I = 73
shift + j = J = 74
shift + k = K = 75
shift + l = L = 76
shift + m = M = 77
shift + n = N = 78
shift + o = O = 79
shift + p = P = 80
shift + q = Q = 81
shift + r = R = 82
shift + s = S = 83
shift + t = T = 84
shift + u = U = 85
shift + v = V = 86
shift + w = W = 87
shift + x = X = 88
shift + y = Y = 89
shift + z = Z = 90

shift + 0 = ) = 41
shift + 1 = ! = 33
shift + 2 = @ = 64
shift + 3 = # = 35
shift + 4 = $ = 36
shift + 5 = % = 37
shift + 6 = ^ = 94
shift + 7 = & = 38            
shift + 8 = * = 42
shift + 9 = ( = 40

shift + - = _ = 95
shift + = = + = 43
shift + \ = | = 124
shift + [ = { = 123
shift + ] = } = 125
shift + ; = ; = 59
shift + ' = " = 34
shift + , = < = 60
shift + . = > = 62
shift + / = ? = 63
shift + ` = ~ = 126

alt + a = å = 229
alt + b = ™ = 153
alt + c = ç = 231
alt + d = ð = 240
alt + f = ƒ = 131
alt + g = © = 169
alt + h = ª = 170
alt + j = º = 186
alt + k = † = 134
alt + l = ¬ = 172
alt + m = µ = 181
alt + o = ø = 248
alt + p = ¶ = 182
alt + q = æ = 230
alt + r = ® = 174
alt + s = ß = 223
alt + t = þ = 254
alt + v = ¸ = 184
alt + w = œ = 156 
alt + x = × = 215
alt + y = ¥ = 165
alt + z = § = 167

alt + 1 = ¹ = 185
alt + 2 = ² = 178
alt + 3 = ³ = 179
alt + 4 = ¢ = 162
alt + 5 = ¼ = 188
alt + 6 = ½ = 189
alt + 7 = ¾ = 190
alt + 8 = • = 149
alt + 0 = ° = 176

alt + [ = ‘ = 145
alt + ] = ’ = 146
alt + , = ‹ = 139
alt + . = › = 155
alt + / = ÷ = 247

shift + alt + a = Å = 197
shift + alt + b =  = 144
shift + alt + c = Ç = 199
shift + alt + d = Ð = 208
shift + alt + f = ž = 158
shift + alt + h = ‚ = 130
shift + alt + i = · = 183
shift + alt + j = „ = 132
shift + alt + k = ‡ = 135
shift + alt + l = ¯ = 175
shift + alt + o = Ø = 216
shift + alt + q = Æ = 198
shift + alt + t = Þ = 222
shift + alt + v =  = 157
shift + alt + w = Π= 140

shift + alt + 1 = ¡ = 161
shift + alt + 2 =  = 141
shift + alt + 3 = £ = 163
shift + alt + 4 = ¤ = 164
shift + alt + 5 = ‰ = 137
shift + alt + 7 = Ž = 142
shift + alt + 8 =  = 143
shift + alt + 9 = € = 128
shift + alt + 0 =  = 129

shift + alt + - = — = 151
shift + alt + = = ± = 177
shift + alt + [ = “ = 147
shift + alt + ] = ” = 148
shift + alt + \ = ¦ = 166
shift + alt + , = ± = 171
shift + alt + . = » = 187
shift + alt + / = ¿ = 191

   !  exclamation mark 
   "  double quote 
   #  hash 
   $  dollar 
   %  percent 
   &  ampersand 
   '  quote 
   (  open parenthesis 
   )  close parenthesis 
   *  asterisk 
   +  plus 
   ,  comma 
   -  minus 
   .  full stop 
   /  oblique stroke 
   ~  tilde 

   :  colon 
   ;  semicolon 
   <  less than 
   =  equals 
   >  greater than 
   ?  question mark 
   @  commercial at 
   [  open square bracket 
   \  backslash 
   ]  close square bracket 
   ^  caret 
   _  underscore 
   `  back quote 
   {  open curly bracket 
   |  vertical bar 
   }  close curly bracket