Number Base Converter
Convert numbers between binary, octal, decimal, hex, and custom bases.
Binary (base 2)
Octal (base 8)
Decimal (base 10)
Hexadecimal (base 16)
Custom base (2–36)
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.
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