Number Base Converter
Convert instantly between binary, octal, decimal and hexadecimal number systems. Very large integers are supported.
What Are Number Bases (Binary, Octal, Decimal, Hex)?
Computers express numbers in different bases. In daily life we use decimal (base 10). Computers work in binary (base 2) at the hardware level. Hexadecimal (base 16) is a compact way to write binary, since each hex digit maps to exactly 4 bits. Octal (base 8) groups 3 bits at a time. This tool converts between all four instantly, entirely in your browser.
Quick Reference
| Decimal | Binary | Octal | Hex |
|---|---|---|---|
| 10 | 1010 | 12 | A |
| 16 | 10000 | 20 | 10 |
| 255 | 11111111 | 377 | FF |
Frequently Asked Questions
Should I prefix a hex number with 0x?
No. Set the input base to Hex and type only the digits (e.g. FF); no 0x prefix is needed.
Can I convert negative numbers?
Yes, just put a - in front of the number.
Are decimal fractions supported?
This tool is designed for integers. Fractional base conversion is not supported.