Number base converter

0 uploads — runs entirely in your browser, works offline

Number base converter — binary, octal, decimal, hex

Enter a number in any base and see it in binary, octal, decimal and hexadecimal at once. It converts in your browser (0 uploads, works offline).

How to use it

  1. Enter your value in the field above.
  2. The result appears instantly.
  3. Copy or Download it.

FAQ

How do I convert a number between bases for free?

Type the number — plain for decimal, or prefixed with 0x for hex, 0o for octal, 0b for binary — and it appears in all four bases instantly in your browser, with no upload.

How do I enter a hex or binary number?

Prefix it: 0xff for hexadecimal, 0b1010 for binary, 0o17 for octal. A number with no prefix is read as decimal.

Is my data uploaded?

No. The conversion is local and nothing is stored; it works offline.

Can I convert several numbers at once?

Yes — tick "one item per line" to convert a list.

Limits

Works on whole numbers. Very large values beyond safe integer precision are not supported.

Related

The byte size converter handles data units; the unit converter covers physical measures.

Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.