Number Base Converter (Binary, Hex, Octal)
Convert numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36 — including very large integers.
How to use
- 1Enter a number and the base it's written in.
- 2See it in binary, octal, decimal, hex and your custom base.
How it's calculated
Uses arbitrary-precision integers (BigInt), so numbers of any length convert exactly.
Frequently asked questions
How do I convert binary to decimal?
Each binary digit is a power of two: 1011 = 1×8 + 0×4 + 1×2 + 1×1 = 11.
Can I include prefixes like 0x or 0b?
Yes. 0x, 0b and 0o prefixes are removed automatically, as are spaces and underscores used as separators.
Are negative numbers and fractions supported?
Negative whole numbers are supported with a leading minus sign. Fractions aren't converted — enter whole numbers.