Base (mathematics)

In mathematics, a base or radix is the number of different digits or combination of digits and letters that a system of counting uses to represent numbers. For example, the most common base used today is the decimal system. Decimal has 10 digits, 0 to 9, so it is a base 10 system.

A base is usually a whole number bigger than 1, although non-integer bases are also mathematically possible. The base of a number may be written next to the number: for instance, ${\displaystyle 23_{8}}$ means 23 in base 8 (which is equal to 19 in base 10).