Computer Number Format - Octal and Hex Number Display

Octal and Hex Number Display

See also Base64.

Octal and hex are a convenient way to represent binary numbers, as used by computers. Computer engineers often need to write out binary quantities, but in practice writing out a binary number such as 1001001101010001 is tedious, and prone to errors. Therefore, binary quantities are written in a base-8, or "octal", or, much more commonly, a base-16, "hexadecimal" or "hex", number format. In the decimal system, there are 10 digits, 0 through 9, which combine to form numbers. In an octal system, there are only 8 digits, 0 through 7. That is, an octal "10" is the same as a decimal "8", an octal "20" is a decimal "16", and so on. In a hexadecimal system, there are 16 digits, 0 through 9 followed, by convention, with A through F. That is, a hex "10" is the same as a decimal "16" and a hex "20" is the same as a decimal "32". An example and comparison of numbers in different bases is described in the chart below.