Number Base Converter

Convert a number between binary, octal, decimal, and hexadecimal. Runs entirely in your browser.

About this tool

Type into any field and the others update automatically. Supports arbitrarily large non-negative integers using JavaScript's native BigInt, so it isn't limited to 53-bit safe integers like a plain number.

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About Number Base Converter

Number Base Converter converts numbers between Binary (Base 2), Octal (Base 8), Decimal (Base 10), and Hexadecimal (Base 16).

How to use Number Base Converter

  1. Enter numeric value into source base input field.
  2. Select source base and target base.
  3. View instantaneous conversion across all four number bases.
  4. Copy converted base string.

Examples

Decimal Input: 255 Binary: 11111111 Hexadecimal: FF Octal: 377

FAQ

What is the maximum integer size supported?

The converter handles standard 64-bit BigInt values without precision loss.

Can I convert negative numbers?

Yes. Negative integers convert using standard sign representation or two's complement.

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