Number Base Converter
Type a number in binary, octal, decimal, or hexadecimal and see it converted to all four bases at once, live as you type. Handles arbitrarily large integers without losing precision, using BigInt-based math.
How it works
Type a number and pick which base you typed it in (binary, octal, decimal, or hexadecimal). The converter instantly shows the same value in all four bases below, recalculated on every keystroke.
Tip
Hexadecimal digits use letters A–F for the values 10–15, and both uppercase and lowercase are accepted. Very large numbers are converted using arbitrary-precision math, so pasting a huge hex value from your code editor won't lose precision.
Why do I get an error for some inputs?
Each base only allows certain digits — binary only 0 and 1, octal 0 through 7, decimal 0 through 9, and hexadecimal 0 through 9 plus A through F. If your input contains a character outside that range for the selected base, you'll see an error instead of a silently wrong result.
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