Number Base Converter Online
Convert numbers between binary, octal, decimal and hexadecimal instantly. Supports huge integers, 0x/0b prefixes and one-click copy for every base.
- BIN(2)
11111111
- OCT(8)
377
- DEC(10)
255
- HEX(16)
ff
Frequently asked questions
How do I convert a number to binary?
Type the number, choose its base (for example DEC) and read the result in the BIN card. All four bases update instantly as you type.
Can I convert very large numbers?
Yes — the converter uses arbitrary-precision integers, so values far beyond 32 or 64 bits convert exactly, without rounding.
Are prefixes like 0x supported?
Yes, you can paste hex with 0x, octal with 0o and binary with 0b — the prefix is recognized automatically.