Number Converter

A number converter between four major numeral systems: binary (BIN), octal (OCT), decimal (DEC), and hexadecimal (HEX). Enter a number in any field — the others will update instantly. Supports arbitrarily large numbers via BigInt.

Numeral Systems in Programming Binary (base 2) is the foundation of computer operation — all data at the processor level is represented as zeros and ones. Octal (base 8) is used in Unix for file permissions (e.g., chmod 755). Hexadecimal (base 16) is used for memory addresses, CSS color codes (#FF5733), and byte representation.

Binary (BIN):

Octal (OCT):

Decimal (DEC):

Hexadecimal (HEX):

Free online number converter between four major numeral systems: binary (BIN), octal (OCT), decimal (DEC), and hexadecimal (HEX). Enter a number in any of the four fields — the others will update instantly.

Binary (base 2) is used in computers for data representation at the processor level. Octal (base 8) is used in Unix systems for file permissions. Decimal (base 10) is the standard system for everyday calculations. Hexadecimal (base 16) is widely used for memory addresses, CSS color codes, and byte representation.

The converter uses JavaScript BigInt, ensuring correct operation with arbitrarily large numbers without loss of precision. Input is validated in real time: only characters valid for the selected numeral system are accepted. Useful for programmers, students, and anyone working with bitwise operations and low-level data structures.