Convert numbers between binary, octal, decimal and hexadecimal. Edit any field and the others update instantly. Large values are exact, with no rounding.
How to use the Number Base
Type a number into any of the four fields.
The other bases update instantly as you type.
Toggle uppercase hex and copy any value with one click.
Frequently asked questions
Binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16). You can edit any of them and the rest follow.
Yes. It uses arbitrary-precision integers (BigInt), so even very long values convert exactly without the rounding errors that affect normal floating-point numbers.
Yes, a leading minus sign is supported. Spaces are ignored, so you can group digits for readability.
No, it converts whole numbers (integers). Fractional base conversion is a separate problem and is intentionally left out to keep results exact.
This number base converter switches integers between binary, octal, decimal and hexadecimal. Every field is editable, so you can start from any base and read the rest immediately.
Conversions use arbitrary-precision integers, so large values stay exact. It is handy for programming, debugging, networking and working with low-level data. Everything runs in your browser.
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