Convert between binary, decimal, hex & octal
Type a number in any field and all other bases update instantly. Decimal (base 10) is the standard number system. Binary (base 2) uses only 0 and 1 — it's how computers store data. Hexadecimal (base 16) uses 0-9 and A-F — commonly used in programming and color codes. Octal (base 8) uses digits 0-7.
255 in decimal = 11111111 in binary = FF in hex = 377 in octal. This tool supports numbers up to 64-bit integers. All conversions happen in your browser — your data never leaves your device.