Number Base Converter
Convert between binary, octal, decimal, hexadecimal and any base up to 36.
Type in any box — the others update instantly. Very large whole numbers are supported.
Runs in your browser — your data never leaves your device.
About the Number Base Converter
Type a number in any box — binary, octal, decimal, hexadecimal or a custom base — and all the others update instantly. Useful for programming, networking, electronics and computer science classes.
Whole numbers of any size are supported exactly, and prefixes like 0x and 0b are understood.
How to use the Number Base Converter
- Type in the box for the base you have.
- Read the number in every other base.
- Change the custom base (2–36) if needed.
How it works
A number in base b is Σ digit × bⁱ. Digits above 9 use letters: A = 10 … Z = 35. Conversion is done with exact big integers, so no precision is lost.
Examples
- 255 = 11111111 (binary) = FF (hex) = 377 (octal).
- Hex
0x1F4= 500 decimal.
Frequently asked questions
Is my data sent to your server?
No. Everything runs in your browser, on your own device. Nothing you type, paste or choose is uploaded or stored.