How to use this calculator
Choose the input base and type digits valid for that base. A leading minus sign is allowed. Results appear in all four bases and can be copied together.
The math behind it
Value = sum of each digit × base^position Convert the same exact integer into bases 2, 8, 10 and 16
A worked example
Hexadecimal FF equals decimal 255, binary 11111111 and octal 377.
Assumptions & precision
Native BigInt arithmetic, so large integers remain exact. Up to 256 input digits plus an optional minus sign. No fractional numbers, exponent notation, 0x/0b prefixes or separators. Hexadecimal output uses uppercase. Changing the selected base reinterprets the entered digits.
A common question
How are negative numbers represented?
With a leading minus sign. This tool does not assume a fixed bit width or generate two’s-complement storage patterns.