Binary, Hex & Decimal Converter

Type a number in any base and see it in binary, octal, decimal and hexadecimal at once, plus any other base from 2 to 36 you choose. Binary output is grouped in fours so it is easy to read against hex digits.

Input is forgiving: 0x, 0b and 0o prefixes are understood, underscores and spaces used as digit separators are ignored, upper and lower case both work, and a leading minus sign is kept. If a digit doesn't belong in the chosen base the tool tells you which one.

The maths uses arbitrary-precision integers, so values far beyond 64 bits convert exactly — handy for hashes, IDs and bit masks that would lose precision in a spreadsheet or a JavaScript number.