Number Base Converter
Convert whole numbers between binary, octal, decimal, and hex
Binary, octal, decimal and hexadecimal
Convert a whole number between the four bases programmers use most. Enter a value in one base and see it in all four. Arbitrary-precision math (BigInt) means even very large numbers convert exactly, with no rounding. Runs locally in your browser.
FAQ
Does it handle very large numbers?
Yes. Conversions use arbitrary-precision integers, so there's no 2⁵³ safe-integer limit and no precision loss.
Can I convert hex letters?
Yes — enter hex digits 0–9 and a–f (case-insensitive) and pick "Hexadecimal" as the input base.
Are negative numbers or fractions supported?
This tool converts non-negative whole numbers only. Decimal points and minus signs aren't accepted.