Free Binary / Hex / Decimal Converter
Convert a number between binary, octal, decimal, and hexadecimal instantly, in either direction.
Your numbers stay in your browser.
How to convert number bases
- Type a number into any field: binary, octal, decimal, or hexadecimal.
- The other three fields update instantly to show the same value in each base.
Why base conversion matters
Binary, octal, and hexadecimal are common ways to represent the same numeric value in computing contexts like memory addresses, color codes, file permissions, and low-level debugging, where decimal isn't always the most useful representation.
Common use cases
- Convert a binary value to decimal while debugging
- Convert a hex color or memory address to decimal
- Check a number's representation across bases while learning
Frequently asked questions
Is this tool free?
Yes. It is completely free, with no signup and no limits.
Is my data uploaded anywhere?
No. Conversion happens entirely in your browser.
What characters are valid for each base?
Binary uses 0-1, octal uses 0-7, decimal uses 0-9, and hexadecimal uses 0-9 and A-F (case-insensitive).
Does this support very large numbers?
Yes. Calculations use JavaScript's BigInt, so it isn't limited to standard 32-bit or 64-bit integer ranges.
Can I convert negative numbers?
No. This tool is scoped to non-negative whole numbers, the most common use case for base conversion.