100% private. Conversions happen entirely in your browser — nothing is uploaded, stored, or sent anywhere.
Developer / Code
Convert between bases
Type in any field — the other three update instantly. Integers only, but as large as you like (arbitrary precision).
When NOT to use Number Base Converter
- It converts integers only — fractions and floating-point values need a different tool, and two's-complement/signed representations are not applied.
- Hexadecimal output uses uppercase A–F without a 0x prefix; add prefixes yourself if your target format needs them.
Questions people ask
Is my input sent to a server?
No. This tool runs entirely in your browser using JavaScript. Nothing you paste is uploaded, stored, or sent anywhere.
How large a number can it convert?
It uses arbitrary-precision integers (BigInt), so values far beyond 64-bit — hundreds of digits — convert exactly, with no floating-point rounding.
What if I type an invalid digit?
Each field validates against its base: a '2' in the binary field or a 'G' in hex shows an inline error and the other fields keep their last valid values.
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