Number Base Converter — Free Binary, Octal, Decimal & Hex Co

Convert numbers between binary, octal, decimal, and hexadecimal with arbitrary precision. Supports fractional and negative values — fully client-side. This free online number base converter runs entirely in your browser — no data is ever uploaded to a server.

How to Use

1. Enter your input — type or paste your a number and its input base.

2. See live results — the tool updates instantly as you type.

3. Copy or download — copy the output to clipboard or download it.

4. History — your recent inputs are saved locally and can be pinned for quick access.

Example

Enter 255 in decimal. The tool instantly shows 11111111 in binary, 377 in octal, and FF in hexadecimal. Copy any output.

Also check out the live tool at freeq.one/tools/base-converter — part of the FreeQ.One suite of free online tools.