$ toolfu run number-base-changer
Number Base Converter — Binary, Octal, Decimal, Hex
Free online number base converter. Convert numbers between binary, octal, decimal, and hexadecimal instantly. See all four bases at once — runs in your browser.
all processing runs in your browser
number-base-changer
input > number
Binary (base 2)
0b11111111
Octal (base 8)
0o377
Decimal (base 10)
255
Hexadecimal (base 16)
0xFF
Number Base Converter — Convert Binary, Octal, Decimal, Hex
Whether you're reading memory addresses in hex, debugging bit flags in binary, or working with Unix file permissions in octal, you constantly need to convert between number bases.
This tool shows all four common bases simultaneously — type a number in one base and instantly see the equivalent in binary, octal, decimal, and hexadecimal. Standard prefixes (0b, 0o, 0x) are included in the output for easy copy-paste.
Common uses
- Converting hex memory addresses to decimal
- Reading and setting binary bit flags
- Understanding Unix file permission octals
- Working with network masks and IP addresses
$ cat FAQ.md
What bases are supported?▶
Binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Enter a number in any base and see it converted to all four simultaneously.
Are prefixes like 0x handled?▶
Yes. Common prefixes (0x for hex, 0b for binary, 0o for octal) are automatically stripped before parsing. The output includes the appropriate prefix for each base.
What's the maximum number I can convert?▶
The tool uses JavaScript's parseInt, which handles integers up to Number.MAX_SAFE_INTEGER (2^53 - 1). For most practical purposes, this covers any number you'd need to convert.