What is binary (base 2)?

Binary uses only the digits 0 and 1. It's the native language of computers because transistors have two states: on (1) and off (0). Every number, character, and instruction in a computer is ultimately stored in binary.

What is hexadecimal (base 16)?

Hexadecimal uses digits 0–9 and letters A–F (where A=10, B=11, C=12, D=13, E=14, F=15). It's widely used in programming because one hex digit represents exactly 4 binary digits (bits), making it a compact way to express binary values. Colors in CSS (#FF5733) and memory addresses are commonly written in hex.

How do I convert decimal to binary?

Repeatedly divide the number by 2 and record the remainders from bottom to top. For 13: 13÷2=6R1, 6÷2=3R0, 3÷2=1R1, 1÷2=0R1. Reading remainders bottom to top: 1101.

What is octal (base 8)?

Octal uses digits 0–7. It was used in early computing when 3-bit groupings were common. It's less common today but still appears in Unix/Linux file permissions (chmod 755).

Conversion

● Conversion

Number base converter

Enter a number in any base — see it instantly in binary, octal, decimal, and hexadecimal.

Input

Value

Base 2 — Binary

0b11111111

Base 8 — Octal

0o377

Base 16 — Hex

0xFF

Decimal value

255

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