Number Base Converter
Free number base converter. Convert numbers between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Supports custom bases from 2 to 36.
Valid digits: 0-9
What Are Number Bases?
A number base defines how many different digits are used to represent numbers. The decimal system (base 10) uses digits 0 through 9, binary (base 2) uses 0 and 1, octal (base 8) uses 0 through 7, and hexadecimal (base 16) uses 0 through 9 and A through F.
Why Convert Between Bases?
Base conversion is fundamental in computer science and programming. Binary is the native language of computers, hexadecimal is used to represent colors and memory addresses, and octal is used in Unix/Linux file permissions.
How to Use This Converter
Enter a number, select the base it is written in, and you will automatically see the conversion to all other bases: binary, octal, decimal, and hexadecimal.
Frequently Asked Questions
What characters are valid in each base?
Binary: only 0 and 1. Octal: 0 through 7. Decimal: 0 through 9. Hexadecimal: 0 through 9 and letters A-F (uppercase or lowercase).
Is there a limit on the number size?
This converter works with positive integers within the safe JavaScript range (up to 2^53 - 1 in decimal).