Number tool
Number Base Converter
Enter a number in any base below — the other three update live.
Where each base is used
Decimal is everyday counting. Binary is how computers represent everything at the hardware level. Hexadecimal is a compact stand-in for binary — each hex digit maps to exactly 4 bits — and shows up in color codes, memory addresses, and hashes. Octal is less common today but still appears in Unix file permissions.