Number base converter

How to use this tool

1. Choose the input base before entering the integer text.
2. Choose the output base and inspect the four common-base representations.
3. Swap converts the value into the new input base before reversing the direction.

Convert beyond the floating-point safe-integer limit

Input and settings

9007199254740993; input base 10; output base 16

Result

20000000000001

The integer is not first coerced to Number, so its final digit is preserved.

How digit symbols are interpreted

Bases above ten use letters A–Z for the additional digits. Input letters are case-insensitive and output letters are uppercase. For example, hexadecimal FF represents decimal 255.

The prefixes 0x, 0b and 0o are removed only when they match the selected hexadecimal, binary or octal input base. Every digit is validated; an invalid suffix is rejected instead of silently converting only the valid beginning.

Signed magnitude versus bit encoding

Negative results retain a leading minus sign, such as -FF. A two’s-complement register representation requires an explicit storage width, which this converter does not infer. Its binary result is a magnitude with a sign, not a signed register dump.

Input is limited to 1,024 digits and excludes fractional points, grouping characters and exponent notation. Exact integer conversion does not validate an operating system’s signed range or a network protocol’s byte order.

Common questions