Number Base Converter
Convert a number between binary, octal, decimal and hexadecimal. Enter a value in any base and see all four instantly — big numbers are handled exactly with BigInt.
Converting between number bases
Binary, octal, decimal, and hexadecimal are just different ways to write the same number. Programmers move between them constantly — hex for colors and memory addresses, binary for bit flags, decimal for everyday values.
Enter a value in any base and see all four instantly. Conversion uses BigInt, so even very large numbers are exact with no rounding. Prefixes like 0x, 0o and 0b are accepted, and everything runs in your browser.
How to use Number Base Converter
- 1Type a value and choose which base it's in.
- 2See the binary, octal, decimal and hex equivalents.
- 3Copy whichever representation you need.
Frequently asked questions
Does it handle very large numbers?
Yes. Conversion uses BigInt, so there's no precision loss even for huge values.
Can I paste hex with a 0x prefix?
Yes — prefixes like 0x, 0o and 0b are accepted and ignored during parsing.
Is anything sent to a server?
No. All conversion happens in your browser.