Online Number Base Converter

Convert between Binary (base 2), Octal (base 8), Decimal (base 10), and Hexadecimal (base 16) — type in any field to convert all others instantly.

Decimal (Base 10)

Binary (Base 2) — digits: 0, 1

Octal (Base 8) — digits: 0–7

Hexadecimal (Base 16) — digits: 0–9, A–F

Number Base Systems Explained

Binary (Base 2): Used internally by all digital computers. Two digits: 0 and 1.
Octal (Base 8): Compact notation for binary. Each octal digit = 3 binary digits.
Decimal (Base 10): Standard human number system. Digits: 0–9.
Hexadecimal (Base 16): Common in programming, memory addresses, colors. Digits: 0–9, A–F.