Binary Decimal Converter — Free Online Tool

🔢 Binary Decimal Converter

Computers store and process everything in binary, but humans mostly think in decimal — and hexadecimal and octal show up constantly in programming, networking and low-level debugging as more compact ways to represent binary data. This converter translates a number between binary, decimal, hexadecimal and octal instantly, so you don't have to work through the place-value math by hand.

It's useful for computer science coursework, debugging memory addresses or colour codes, working with bitwise operations, or simply understanding how a familiar decimal number looks in another base.

How to use the Binary Decimal Converter

Enter a number and select which base it's currently in (binary, decimal, hex or octal).
The converter instantly shows the equivalent value in all the other three bases.
Copy any of the converted values with one click.

How base conversion works

Any number in a given base is converted to decimal first by summing each digit multiplied by the base raised to its positional power — for binary, that means summing powers of 2; for hex, powers of 16; for octal, powers of 8. That decimal value is then converted into the other target bases using repeated division-and-remainder, which is the standard algorithm for base conversion.

Frequently asked questions

Why does hexadecimal use letters A–F?

Hexadecimal is base 16, so it needs 16 distinct digits. After 0–9 are used up, the letters A through F represent the values 10 through 15, keeping each digit to a single character.

What's the binary equivalent of a byte?

A byte is 8 bits, so it can represent decimal values from 0 (00000000 in binary) to 255 (11111111 in binary). This converter will show you the exact binary pattern for any decimal value you enter within that range and beyond.

Does this handle negative numbers?

This converter works with non-negative integers using standard positional notation. Representing negative numbers in binary typically requires a specific convention like two's complement, which depends on a fixed bit-width and isn't part of this general-purpose converter.