A numeral system is a notation for representing numbers. In mathematical numeral systems the base or radix is usually the number of unique digits, including zero, that a positional numeral system uses to represent numbers. For example, for the decimal system the radix is 10, because it uses the 10 digits from 0 through 9. When a number hits 9, the next number will not be another different symbol, but a 1 followed by a 0. In binary, the radix is 2, since after it hits 1, instead of 2 or another written symbol, it jumps straight to 10, followed by 11 and 100. This Numbers converter allows you to convert binary, octal, decimal, hexadecimal, base-2, base-3, base-4, base-5, base-6, base-7, base-8, base-9, base-10, base-11, base-12, base-13, base-14, base-15, base-16, base-17, base-18, base-19, base-20 among other units related to Numbers.