Number Base Converter
Convert between binary, octal, decimal, and hexadecimal
About Number Bases
A "base" or "radix" is the number of unique digits used to represent numbers. Decimal (base 10) uses 0–9. Binary (base 2) uses 0–1. Hex (base 16) uses 0–9 and a–f. The number itself is the same — only the notation changes.
This tool uses arbitrary-precision integers, so very large numbers convert exactly without loss of precision. Useful for working with binary file headers, hex color values, network masks, computer science homework, or anywhere you need to switch representations of an integer.
Frequently asked questions
Does it support negative numbers?
Yes — prefix the value with a minus sign in any base. The output bases will all show the same negative sign convention (not two's complement).
What about decimals or fractions?
This tool handles integers only. Most non-decimal bases require careful handling of fractional parts, and the typical use case (programming, color codes, addresses) is whole numbers.