Binary Converter
Convert signed integers between binary and decimal exactly, up to 10000 digits. Check examples, preserve large values and copy the result.
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Binary Converter
The direction selector provides exactly two operations: base-2 integer to base-10 integer, and base-10 integer to base-2 integer. It is not the separate arbitrary base 2-36 converter.
Conversion uses JavaScript BigInt with manual digit parsing, so integer precision is retained beyond Number's safe-integer range. Input is capped at 10,000 digits to bound browser work and memory.
Verified examples: binary 101101 converts to decimal 45; decimal 45 converts to binary 101101; binary -101 converts to decimal -5. Leading zeros are accepted but are not retained in the normalized result.
Binary input permits only 0 and 1 after an optional leading minus sign. Decimal input permits only digits after an optional leading minus sign. A bare minus sign, fractions, scientific notation, prefixes such as 0b, embedded spaces and invalid digits are rejected.
Negative output uses a leading minus sign, not two's-complement or a fixed bit width. The page does not convert fractional binary values, floating-point layouts, text bytes or bitwise representations. Conversion runs locally in the browser and does not upload the integer.
Choose the right tool
- Integer Base Conversion Table
Convert integers between binary, octal, decimal, hexadecimal and other supported positional number bases.
- Binary Converter
Convert between binary and decimal
- Hexadecimal Converter
Convert between hexadecimal and decimal
Use ASCII digits; localized numeral shapes and a leading plus are not accepted. The 10000-digit limit excludes an optional minus and outer whitespace; embedded whitespace is rejected. Only the converted target is normalized: the left side of the displayed equation retains the input, so 00101 (base 2) =5 (base 10).
Processing takes place locally in your browser.