Number Base Converter

About This Tool

Computers use four number bases most often: binary (base 2) — digits 0-1, the native language of CPUs; octal (base 8) — digits 0-7, used in Unix file permissions; decimal (base 10) — the everyday number system; and hexadecimal (base 16) — digits 0-9 and A-F, used in memory addresses, colors, and byte representations.

To convert, enter any number and select its base. The tool instantly shows the equivalent in all four bases. Negative numbers are supported — enter a minus sign before the digits.

How to Use

1. Enter a number in the input field.
2. Select the input base (binary, octal, decimal, or hex) from the dropdown.
3. The converted values in all four bases appear instantly.
4. Click the copy button next to any result to copy it to the clipboard.

Use Cases

Developers convert memory addresses and hex values to other bases. Students learn number base conversion in computer architecture courses. Security researchers analyze binary data. System administrators check octal values for Unix file permissions.

FAQ

• What do A-F mean in hexadecimal? In hex, A=10, B=11, C=12, D=13, E=14, F=15. Since each hex digit represents 16 values, letters are used for 10-15.
• Can I convert negative numbers? Yes. Enter a minus sign before the digits. For example: -255 (decimal) → -FF (hex).
• Why is hex used for color codes? RGB color channels each range 0-255, which is 00-FF in hex. Two digits represent a full channel value, making #RRGGBB a natural fit.