Number Base Converter
Convert numbers between binary, octal, decimal, hex, and custom bases.
About the Number Base Converter
Live-sync a number across binary, octal, decimal, and hexadecimal, plus any custom base from 2 to 36, using arbitrary-precision BigInt math so large numbers stay accurate.
Popular uses
- number
- base
- binary
- hex
- octal
- converter
Examples
Decimal 42
42Output
0b101010 / 0x2aKeyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Version 1.0.0 · Updated 2026-08-06 · Runs entirely in your browser