Number Base Converter

Convert a number from any base between 2 and 36 to binary, octal, decimal, hexadecimal and a base of your choice.

Results update as you type.

Decimal

255

from base 10

Binary
1111 1111
Octal
377
Hexadecimal
FF
Base 36
73

About this calculator

Large numbers are converted exactly, without rounding.

How to use it

  1. Enter the number.
  2. Choose its base.
  3. Choose another base to see, if you like.

The formula

Value = Σ digit × baseposition
base 36
uses 0–9 and A–Z

Worked example

255 in decimal

  1. Binary 1111 1111, octal 377, hex FF.
  2. Base 36: 73.

What the result means

Binary is grouped in fours so it lines up with hex digits.

Assumptions

  • Whole numbers.

Limitations

  • Fractions are not converted.

Frequently asked questions

How do I convert decimal to binary?

Divide by 2 repeatedly and read the remainders from bottom to top.

What is 255 in hex?

FF.

What is base 36?

Digits 0–9 then A–Z, used for short codes.

Last reviewed on 3 October 2026. Found a mistake? Tell us.