Number Base Converter

Convert numbers between decimal, binary, octal, hexadecimal and any base from 2 to 36. Includes bit grouping and quick presets — the everyday companion for programmers.

100% free No uploads Runs in your browser No signup

Number base converter

Number

Input base

Base 2 (binary)

11111111

Base 8 (octal)

377

Base 10 (decimal)

255

Base 16 (hexadecimal)

All at once

bin: 11111111 oct: 377 dec: 255 hex: FF

Supports every base from 2 to 36 (letters a–z as digits). Values up to 2⁵³−1 are exact; the input automatically accepts 0x, 0b and 0o style prefixes for their matching bases.

How to use the Number Base Converter

1
Open the tool above — it is already running, no install or account needed.
2
Enter your input and adjust the options to match what you need.
3
Copy or download the result — everything was processed locally in your browser.

Private by design

This tool runs 100% inside your own browser using local JavaScript — your input never touches a server. That makes it instant, offline-capable in many cases, and private even for sensitive data.

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