Number Base Converter
Convert numbers between decimal, binary, octal, and hexadecimal — type in any field and the other three update live.
How to Convert Between Number Bases
- Type a number into any one of the four fields: Decimal, Binary, Octal, or Hexadecimal.
- The other three fields update instantly with the equivalent value in their base.
- Each field only accepts valid characters for its base, so typos are filtered out automatically.
- Clear a field to reset all four fields, then start fresh.
Frequently Asked Questions
Does this support negative numbers?
No — this tool only supports non-negative integers (0 and up). Binary, octal, and hexadecimal representations of negative numbers depend on a chosen bit width and encoding (like two's complement), which varies by system, so supporting negatives correctly would require assumptions this tool can't make on your behalf. Stick to whole numbers of zero or greater.
What happens if I type an invalid character?
Each field filters out characters that aren't valid in its base as you type — for example, the binary field only accepts 0 and 1, and the octal field only accepts 0-7 — so you can't enter something that field's base can't represent. If a field ends up empty or unparseable, the other three fields are simply cleared instead of showing an error.
Why does the hexadecimal output use uppercase letters?
Uppercase hex digits (A-F) are simply this tool's display convention and are the most common style in documentation and programming references. The hex input field itself accepts both uppercase and lowercase letters.
Is there a limit to how large a number I can convert?
This tool uses standard JavaScript number parsing, which reliably handles integers up to 2^53 - 1 (9,007,199,254,740,991). Beyond that, floating-point precision limits mean extremely large numbers may lose accuracy.
Do I need to click a button to convert?
No — conversion happens instantly as you type in any of the four fields. There's no convert button because the whole point of this tool is live, no-click conversion.