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About Number Base Converter Online
This tool converts numbers between bases: binary (base 2), octal (base 8), decimal (base 10), hexadecimal (base 16), and any other arbitrary base from 2 to 36. Enter a number in one base and see it in all the others.
Base conversions are fundamental in programming and computer science. Memory dumps and assembly use hex; permission bits and Unix file modes use octal; raw bit-level work uses binary. Being able to switch fluidly between representations saves hours of mental arithmetic.
Use it when reading assembly listings, debugging bitwise operations, working with file permissions, or studying for computer architecture exams.
How to use this tool
How to convert a number between bases (2–36)
Enter the value
"Value" is the number to convert, written in the FROM base. Whitespace is stripped, so `dead beef` and `deadbeef` parse the same. Digits A–Z represent values 10–35, case-insensitive.
From base / to base
"From base" and "To base" are integers between 2 and 36. Common: 2 (binary), 8 (octal), 10 (decimal), 16 (hex), 32 (Base32), 36 (max — uses 0–9 + A–Z).
Press Run
Result is a single `result` field — the value rendered in the target base, lowercase for letters. Invalid digit for the FROM base throws "Invalid digit for source base."
Watch the precision limits
Parsing uses JavaScript `parseInt`, which is limited to 32-bit safe integers in many contexts. Very large numbers (above 2^53) lose precision — use a big-integer tool for those.