Number Base Converter
Convert a number between any two bases from 2 to 36 - binary, octal, decimal, hex, or any custom base.
Enter a number, its current base, and your target base (2-36) - this tool converts it accurately using BigInt arithmetic.
Supports bases 2-36 (using digits 0-9 and letters A-Z). Only integer values are supported, and results are limited to JavaScript's safe integer range (2^53-1).
For the most common conversions specifically, the dedicated Binary/Hex/Octal converters may be quicker to use.
What Is a Number Base?
A number's base (or radix) determines how many unique digits it uses and what each position is worth - binary is base 2, octal is base 8, decimal is base 10, hexadecimal is base 16, and any base from 2 to 36 is possible using digits 0-9 and letters A-Z for values above 9.
How to Use It
- Enter a number and select its current base.
- Select the target base (2 to 36).
- The converted value appears instantly - digits invalid for the selected source base are flagged.
Limitations
This converts non-negative whole numbers accurately for arbitrarily large values using BigInt - fractional values in non-decimal bases aren't supported, since their interpretation varies and isn't universally standardized.