Number Base Converter

Convert between binary, octal, decimal and hexadecimal in one step.

Decimal
2,026
Binary11111101010
Octal3752
Hex7EA

About the Number Base Converter

Whether you are studying computer science, debugging a colour code, or reading a memory address, the AlarmDaddy Number Base Converter switches a value between binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16) at once. Pick the base you are starting from, type the value, and see it in every other base.

The converter validates the digits against the base you chose, so a stray "2" in a binary number or a "G" in hex is caught rather than silently truncated. It is built for the everyday conversions programmers and students need most, and runs entirely in your browser.

How to use this tool

  1. 1Select the base of your input (binary, octal, decimal or hex).
  2. 2Type the value.
  3. 3Read the equivalent in all four bases.

The formula

Each base uses a fixed set of digits; the value is parsed to an integer, then re-expressed in the target base.

A number in any base is a sum of its digits times powers of that base. The converter parses your input into a plain integer, then formats that integer in binary, octal, decimal and hexadecimal. Inputs are validated against the allowed digit set for the chosen base.

Frequently asked questions

255 in decimal is FF in hexadecimal, 11111111 in binary and 377 in octal.