Number Base Converter

This free number base converter translates a number from any base to any other base, from binary and octal through decimal, hexadecimal and every base in between (2–36). Pick a “from” and “to” base, hit Convert, and copy the result — or use Swap to reverse the direction instantly. An “all bases at once” panel always shows the value in binary, octal, decimal and hex side by side, each with its own copy button.

Unlike most online converters, this one uses arbitrary-precision integers, so numbers far larger than 2⁵³ convert exactly instead of silently rounding. It also converts fractional numbers (for example1010.11 in binary) with an adjustable number of fraction digits, and it accepts common prefixes (0x, 0b,0o) plus digit separators (spaces, underscores or commas) in the input. Toggle digit grouping and upper/lower case on the output.