Hexadecimal Converter
Convert signed integers between hexadecimal and decimal with BigInt precision. Supports up to 10000 digits; copy the result.
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Hexadecimal Converter
Converts signed integers in either direction between hexadecimal base 16 and decimal base 10. The direction selector is explicit; verified decimal 255 converts to hexadecimal FF.
Parsing and formatting use BigInt for exact integers beyond JavaScript's safe-number range. Hexadecimal accepts digits 0-9 and A-F case-insensitively, and output letters are uppercase.
Input may have one leading minus sign and up to 10,000 digits. Prefixes such as 0x, plus signs, spaces inside the number, fractions, byte strings and hexadecimal floating-point notation are rejected.
The result displays both the original and converted bases using ASCII digits. This page does not encode text as hexadecimal, decode bytes, calculate two's-complement signed widths or add padding; use the ASCII/hex or developer conversion tools for those tasks.
Conversion is local to the browser and does not transmit the input. For protocol or binary-file work, confirm the required bit width, sign representation and byte order independently because this tool represents mathematical integers only.
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
The 10000-digit limit excludes a leading ASCII minus sign and outer whitespace. Outer whitespace is trimmed; internal spaces and grouping separators are invalid. Use ASCII 0–9, not localized digits. Converted output removes leading zeros; -0 becomes 0. In hexadecimal, 1e3 is an integer equal to decimal 483, not scientific notation; in decimal mode it is invalid. Changing direction requires another click on Convert. Clear empties the input/result and keeps the direction.
Processing takes place locally in your browser.