Number Base Converter
Convert between binary, octal, decimal, and hexadecimal instantly.
Type in any field — the other three update automatically. Supports numbers of any size.
Frequently asked questions
Is there a limit to how large a number I can convert?+
No practical limit — this uses arbitrary-precision integer math internally, so it isn't restricted to the roughly 9-quadrillion ceiling that ordinary JavaScript numbers hit.
Does this support negative numbers or decimals?+
No — this converts non-negative whole numbers only, which covers the overwhelming majority of binary/hex/octal conversion needs (memory addresses, color codes, bitmasks, and so on).
Do I need a 0x or 0b prefix?+
No — just type the digits for that base (e.g. "ff" in the hex field, not "0xff"). Hex accepts both upper and lower case letters.