Number Base Converter

What the Number Base Converter does

The Number Base Converter converts a number between binary, decimal, hexadecimal, and octal, letting you enter a value in any of the four bases and see it instantly translated into the others.

How to use it

1. Enter the value you want to convert.
2. Select which base the value is currently in.
3. The converted values in the other bases appear automatically.

Common uses

• Converting a hex color code or memory address into decimal for readability.
• Working through binary or hexadecimal homework for a computer science course.
• Checking a permissions value (like Unix chmod octal codes) against its decimal equivalent.
• Debugging a bitwise operation by inspecting a value's binary representation.
• Converting a hex value from a debugger or log file into a readable decimal number.

Good to know

Hexadecimal uses digits 0–9 and letters A–F, so an input like "1A" is only valid when hex is selected as the source base — entering it as decimal or binary will show an error, since neither of those bases uses letters.

Different number bases exist for practical reasons tied to how computers actually work — binary (base 2) directly reflects how data is stored at the hardware level, hexadecimal (base 16) is a compact way to represent binary data since each hex digit maps to exactly 4 bits, and octal (base 8) was more common in older computing systems built around 3-bit groupings. Understanding these conversions is a foundational skill in computer science precisely because so much of how computers represent data ultimately traces back to these base systems.