Published Apr 2, 2023
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Hexadecimal (hex, hex numbers, or base-16) is a number system that uses a base of 16 as opposed to the standard decimal system, which is base 10. When representing a number, both number systems share the first ten digits, 0-9. However, for hexadecimal, the remaining digits 10-15 are represented by the letters A-F (not case sensitive)

Decimal Hex
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 A
11 B
12 C
13 D
14 E
15 F

Power Of 2

Hexadecimal, as well as binary (base 2) and octal (base 8), have bases that are powers of two, making it easy to convert between one another.


A hexadecimal number is prefixed with 0x in many computer languages to identify it as a base 16 number.

Hex Colors

Hex numbers are often used to represent colors (hex colors) and are specified in the following way: #RRGGBB(red, green, and blue). One example of a hex color is #0000FF which represents the color blue. This is because red and green are set to their lowest value, 00, and blue is set to its highest value, FF.

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