You reached us perhaps looking for answers to questions like: ASCII question mark or maybe, how to encode question mark in ASCII? The decimal code for question mark is 63. This is equivalent to the hexa-decimal number 3F and the Octal 77. Here is the information about the ASCII code for question mark (?):
Description: question mark
The ASCII character set consists of 128 characters (0 to 127 decimal, 0 to 7F hexadecimal, and 0 to 177 octal). In the 1st column are the characters as they are show in a HTML page. In the second column the decimal code. The 3rd and 4th columns shows the decimal to hex and octal conversion. Note that 32 characters (from 0 to 31) are control characthers (originally non printable chars). They are used, mainly, in data communications to control the information flow in a data line. Actualy, you can type for exmple 'alt + 14' (numeric keyboard) in a windows application and get this symbol ♫ on your screen, but this does not mean that it is a printable ASCII character (Some people call them 'ALT Codes' and the resulting character dependes on your opersting system (windows, linux etc.).